Need advice on multiple symptoms (*long post*)

I have had multiple symptoms for many years and there has been no definite explanation of cause. I would very much appreciate any suggestions or advice on what could be wrong or tests I should ask for. Thank you.

I have had multiple blood tests, stool and urine tests, chest x-rays, a 24 hour heart monitor, and multiple EKG’s. Nothing useful has been found. I am currently on lexapro. Doctors seem to shrug me off or minimize the severity of effect it’s having on my life. They seem patronizing at times using terms like: high strung, overly sensitive or that it’s “just anxiety or depression”. I know I tend to be pessimistic and anxious but, i really feel like there is a physical, correctable cause and I need to find it. In addition, my mom and sister have also had many of the same symptoms for many years.

I will try to be as brief as possible. I am a 37 yo female. As a child I feel I was healthy and averagely active; spent the whole summer outside. Had no allergies (other than from mosquito bites, but who doesn’t?). If I got sick I did the typical: rest, fluids, meds if necessary and I got better.

At 10: I got mononucleosis. It lasted for a year or so. During the illness I had: fever of over 104, chills, severe sore throat; body aches especially in lymph nodes, swollen lymph nodes, and exhaustion.
The exhaustion improved, but never went away. I never got back the childlike energy I had before that.

At around 11: myself along with three relatives in the same house would occasionally get blue coloration on our hands (peripheral cyanosis) (and once I had it on my face under my nose). It would last from a few minutes to a few hours. We had no other symptoms and it only occurred for a few months.

During teenage years: it seemed like each time I needed antibiotics my stomach became more and more sensitive to them, and, to everything in general.

At 14: I had a bout with a bad stomach virus. For the first time I began having severe dizziness and fainting with any severity of diarrhea, vomiting or sometimes just nausea. This has remained the case.

At 20: I got a stomach virus the doc called a rotavirus. Had severe stomach cramps, diarrhea and vomiting and went to ER. Was admitted and given intravenous fluids and anti-nausea medication.

For the past 10 years or so I occasionally get what I can only call “episodes”. They happen both while awake and awaken me from a sleep:
Rapid heart rate (110-130 bpm)
Palpitations
Shortness of breath
Nausea
A feeling of needing to flee or
A sense of impending doom
Shaking
Chills
Feeling the need to have a bowel movement (sometimes I go, sometimes not)
These “episodes” last from about ten minutes to an hour.

Over the years I have developed these symptoms; listed in order of development the best I can remember:
•Digestive issues (upset and sensitive stomach with no apparent reason; constipation with occasional bouts of diarrhea; acid reflux; feeling and looking bloated)
•Anxiety (acute at times, over the years I’ve learned to quash it enough to function…most of the time)
•Headaches &/or Body Aches for no known reason
•Heavy, painful periods until beginning birth control.
•Rapid heart rate &/or palpitations as if my heart is “fluttering”
•Lightheadedness & Dizziness (even stooping and standing back up is a problem)
•Fainting
•New and worsening allergies: seasonal, insect bites/stings, pet dander, sun exposure, poison ivy, products used on skin: soaps, lotions, etc. (as a reminder, I had almost none of these growing up)
•Steady Weight Gain (I am 5’ 3” and currently 175 lbs.)
•Lack of motivation
•Dry, itchy skin
•Swelling of hands and feet
•Puffy, round face
•Shortness of breath
•Sugar cravings
•Depressed, hopelessness, sadness
•Sensitivity to both cold and heat; others can be comfortable when I am not
•Sensitivity to pain (sometimes a small pinch can be painful when I know it shouldn’t be)
•Sleep difficulties; trouble falling or staying asleep or sleeping too much.
•My hair has changed a lot in texture; from silky, thick and fast growing to dry, frizzy, fine and falling/breaking…also gray 🙁
•Excessive daytime sleepiness
•Jaw clenching & pain; the pain is literally constant and there are multiple palpable knots in my jaw area.
•Neck & shoulder pain and knots
•Increasing irritability and lack of patience; I used to be a very patient person, now I can fly into a rage over a jar I can’t open;
•Mental Fog; this really concerns me; I can’t focus, remember or comprehend, and it only seems to get worse.
•Fatigue. I should list this first as it is by far the worst symptom, but it was later to come about. I can hardly get through the basic tasks of the day. I no longer enjoy things; almost nothing really because I don’t have the physical or mental energy.

Some of these things may or may not be related and some may simply be symptoms of aging. But these symptoms, especially the fatigue, are literally sapping my will to live. I feel useless, stupid, weak, and lazy, and I am a terrible burden on my husband. Lately, I can think of a million reasons everyone would be better off without me, and almost no reason I am useful. I can’t keep being so unproductive. I can’t keep existing like this.