Head feels like it will explode daily. Severe cognitive difficulties

You need a specialist.

I'm so so sorry for what you are going through. I can give you my experiences that may or may not mean anything for you... Maybe you can contact The Hydrocephalus Association. I guess your neurologist didn't see any problem with fluid on your brain. But maybe they know of a specialist in your area that could see you and rule it out for sure.
Now, my experience. I remember the same kind of pain you describe. I had a root canal done on my far back upper tooth. He cleaned out 1 root but left 2 that got infected.. I did not find this. out until years and years of constant sinus infections and migraines. I had a 3D image of the tooth in front of it that needed a root canal, and the dentist was confused why I had a partial root canal that was done and obvious infection in 2 of the 3 roots left. I went back to my dentist who asked if that tooth had direct pain. I said no. And he said it was ok , because that infection would stay in the tooth area and never be a problem... After a year of further migraines and sinus problems that got worse and worse, I decided on my own to try to find a dentist surgeon who could remove that back upper tooth, even though it would effect my bite.
I never expected what would happen. The day I had that tooth removed. I could barely breath out of the right side of my nose for years.... The right side completely cleared. My severe headache was gone. I walked out of the office and my vision was greatly improved. I had worn glasses to drive for over 10 years. I could suddenly read license plates and street signs and didn't need the glasses at all. While the area was still draining this continued. After 4 days the headache returned, but less severe . And over 10 years later , now over 70 yrs old, my vision is starting to blur a bit. Expected with age i guess... But the only headaches I get now I believe are basically triggered by allergies. I can change my diet and they will go away..... Maybe contacting a good allergist could find something too..... sometimes a chiropractor can help if I've overdone yard work etc.
I know how frustrating struggling to find a doctor who wants to keep looking for answers with you. I used to think posting on this Mayo sight might wake up some doctors at Mayo that might read and discover some answers..... But I really don't believe any doctors from Mayo look at this sight... I'm really not sure what it's for. Just frustrated suffering people that get no help from the words MAYO CLINIC.
I'm praying for you. You are so young. I guess I believe in miracles, because that's what I felt when I got a tooth pulled that had been infected over 20 years with No dentist ever noticing. Only a 3D image found it which your regular dentist will never look that deep at your roots.
It could be a simple answer I'm hoping for you. Try to track what you eat. What was going on when it started .. I know over the years things made my headaches worse. Eating Ranch dressing, smelling bleach or eucalyptus. I've always tried to use everything unscented. But I don't have to do that as much anymore.
There's a book called " Is This Your Child" , about things that trigger children's actions. I believe the same kind of things can trigger headaches.... I never found a doctor who actually tried to find a cure for my headaches. Only drugs.... Which somehow I never accepted taking the DAILY meds to prevent migraines. I always said, why take drugs every day, if I go 2 weeks now with no headache. What effect does a daily drug do, if it really doesn't get rid of the headache.... and it never did......
Keep looking for answers. I have found a chiropractic adjustment could make my headaches dramatically better, but you have to be careful, because they have made it dramatically worse too... It has come to a 50/50 on that now... I don't let them adjust my neck because my neck bones are messed up and too fragile for that. but back adjustments do help....
Take care.... please.... I know people around you don't always understand when they are blessed with NO headaches..... please keep looking.... track your food and surroundings maybe....
I quit looking on this sight for years because it never helped. But I'm not sure why I looked today. Maybe a reason? Praying for answers for you.

OH... just to let you know. I was a flight attendant for 30 yrs. There are drugs you can't take and fly.. Headaches and flying was a challenge. Luckily it was a flexible job too. I did find out after taking darvocet for over 5 years ( the only drug available back then for headaches) that it was really making my headaches worse.. a lot worse... at that time I quit taking it because I knew it didn't help. Then is when I realized it made it worse.... The fewer drugs the better..... I cannot take tylenol at all because I took so much for years. Only Advil work now...
I never took antidepresents. Read the side effects of your meds , AND BELIEVE THEM. I know doctors completely ignore side effects. I don't. I know codeine makes my headaches worse, yet a doctor wrote a prescription for cough med with codeine. Track things.... I took imitrex for years. Was a miracle drug, but when generic started, I found I could only take generic from 1 supplier, but 2 others didn't work... I had to stop the imitrex after a couple years because now it causes chest pains.... But Advil seems to be fine for me now.
So sorry if this is too much info........................... years of experience is a lot, but I believe you can find a trigger and never have to have all this EXPERIENCE.....
rooting for you... You WILL find it...... take care........ T

I am so sorry to hear what you're going through. This is far too much, and at such a young age. It's clear you are self reliant, determined, and intelligent. These skills will help you while you progress through your journey towards health. Please do not give up! Although you may feel it's hopeless at times (I certainly did and continue to at times), there's always the possibility for healing with the right help and support.

I am a 61 year old female and have a history of vestibular migraines going back 7 years. After seeing multiple neurologists, they discovered I have what's called transverse sinus stenosis, resulting in a condition named Idiopathic Intracranial Hypertension. Although I had multiple MRIs, it wasn't until a neurologist who specialized in tinnitus (I experience this intermittently) ordered an MRV of my brain that they discovered this. Since I was diagnosed, I've read reports of younger people with this condition who were helped tremendously by a procedure that involves placing a stent in the sinus vein.

I also want to mention that some of your symptoms sound like they're related to a dysregulated nervous system. I experience this due to an autoimmune disease and it's been a struggle, but I'm learning more and beginning to understand how to help ease some of my symptoms. I recommend you begin to research both of these conditions (idiopathic intracranial hypertension and dysregulated nervous system) and see if anything sounds familiar. If not, it's another thing you can check off your list. If so, it may provide some leads for you to pursue.

I've included some links to studies below, as well as links to two books that have helped me a lot. The first (Brave New Medicine) is written by a female doctor who experienced a debilitating illness that was extremely difficult to diagnose and treat. It gave her an entirely new perspective on the limitations of traditional approaches to medicine and, over time, she was able to heal herself. Although you may not feel you have anything in common with the author, this book may give you hope and make you realize you are not alone—nor is this all in your head. The second book, The Nervous System Reset, provides an excellent overview of the autonomic nervous system, as well as exercises to help balance dysregulation. This has helped me a lot. I checked them both out from my local library and eventually purchased them for reference.

One last thing I want to mention is that I now pay careful attention to my water intake, since dehydration will quickly result in a headache. Are you drinking enough water? If not, this is something you can try immediately. It's free, accessible, and my provide some relief. Also, what about your diet? I have to be super careful about what I eat, which allows me to live my life. Are you eating a healthy, balanced diet? Have you tried keeping a food journal to see if there's a correlation between food and your headaches and other symptoms? If not, something else to consider.

I hope you're able to locate someone to help guide you towards health and healing, and that you're able to find relief.

-SA

Idiopathic intracranial hypertension in males
https://pmc.ncbi.nlm.nih.gov/articles/PMC5946368/
Transverse Sinus Stenosis as an Underdiagnosed Cause of Chronic Headache: A Case Report
https://pmc.ncbi.nlm.nih.gov/articles/PMC11410061/
Chronic Stress and Headaches: The Role of the HPA Axis and Autonomic Nervous System
https://pmc.ncbi.nlm.nih.gov/articles/PMC11852498/
Brave New Medicine
https://www.amazon.com/Brave-New-Medicine-Unconventional-Autoimmune-ebook/dp/B07MQXR5DC/ref=sr_1_1?crid=1RCUPEQXCD56J&dib=eyJ2IjoiMSJ9.vVnAoHQ1WOxbzMjAvpD_YWpIF7heh0-m7K-IcQHiyh1zDb8FhdzZIlHrcehpYzyA.Qnr7xtIXMbRvf-Cvpk0XS-cNaQ4nrzCUMHDDAmvRWM0&dib_tag=se&keywords=Brave+New+Medicine&qid=1745008601&s=digital-text&sprefix=brave+new+medicine%2Cdigital-text%2C273&sr=1-1
The Nervous System Reset
https://www.amazon.com/Nervous-System-Reset-Regulate-Emotions-ebook/dp/B0CK8D3YCR