I usually get sinus pressure headaches at night, at times severe. I usually apply a heating pad and take acetaminophen and a decongestant.
Are you only having headaches at night?
Did you see a Neurologist when you had the MRIs?
As you know there are different types of headaches, such as tension, cluster and migraines- there probably are more.
It appears to be a vicious cycle- if you don’t get enough sleep, chances of getting a headache are large. If you have a headache- you can’t sleep.
A good Neurologist should be able to tell what type of headaches you have. There are also several different medications used to bring good sleep back, and then headaches will lessen too.