A History for Comparison
I am 66 this year & have had (obvious but undiagnosed) POTS since my earliest years. It has gone through 3 major stages.
As a young child it mainly showed only as an inability to run & keep up with the neighborhood kids. We'd run until everyone was winded, but in a minute everyone else would be gone. I'd be left by myself as they would run off as I could not catch up.
It was probably during this phase or nearly the next one when the gastroparesis began to be noticeable. I often complained about my stomach, was seldom hungry. From my parents point of view I was simply seen as a fussy eater. I didn't really have the vocabulary to explain properly, but do recall telling my mother that my "stomach has gone on strike".
The next phase saw the symptoms multiply as I entered my early teen years. Blacking out as I got up from sitting became the most prevalent symptom but was joined by such things as difficulty climbing stairs, lifting heavy objects or standing for extended periods. Running continued to be a problem. I never finished a 600 yd. dash in school in my life...I always came limping in at the end with the heavier and asthmatic kids.
During this period I was taken to numerous doctors. Opinions ranged from "we don't have a clue" to "it's all in your head". There was, however, one doctor's assistant who did an impromptu test for POH (Postural Orthostatic Hypotension) which proved inconclusive & was never pursued.
Oddly, I took up hiking, simply because I enjoyed the trips. Physically, they made me feel horrid, like one long stair climb. I moved very slowly & took long rests. Definitely never did group hikes! But I just liked to be outdoors so much. My heart always acted very badly the day after a hike.
Now I am in a 3rd, highly disabling stage. I doubt it is caused by the POTS itself but probably an interaction between the ailment & another hidden illness (I avoid doctors these days...very long story). I have been gradually getting worse for about 8 years. I used to do nearly ALL the work in the household but now I do practically none. I do whatever small chores I can to be helpful to my wife as she cooks (used to be my job). I remember when I could only pick up a half-gallon jug...then a quart, then finally I cannot get a light plastic cup of drink for myself. My wife must pour it & put it on my stomach. Then I need to use extraordinary means to get it to my lips without actually picking it up.
Lastly I will just say that I am extraordinarily intuitive. I didn't know what POTS was until last August...I read an article (possibly on this site) and said "Hey! That's ME!!". But a year or so before that I began to notice that most of my issues (anxiety, panic attacks, migraine-like headaches, my heart not being able to catch-up, etc...) all seemed to be originating from the same area of my brain. Which I now can label as the area which contains the functions known as the autonomic nervous system.