I can identify Roland.
I have a weird spinal condition that is very rare, and causes all sorts of things that doctors can't typically help a whole lot with.
Half my life on and off I had that kind of crippling "I want to die"intestinal pain. Weirdly enough for me it turned out to be lack of exercise, combined with a certain dietary combination, it still happens on occasion though. In the last few years I've twice burst an eardrum, so now I have severe Tinnitus, which took some getting used to, can make you crazy at first - definitely a problem for which no medical solution exists. After that I got some weird neurological problem with my shoulder that made my arm difficult to move, twitchy, and in pain constantly..they never figured out what it was, tincture of time and an elimination diet for a number of months and it finally got better. Most recently, I've spent the last year recovering from an H. Pylori stomach infection..which was easy enough to clear up with antibiotics..but the symptoms lasted a year anyway, despite the GI doctors claim that I should be normal again after the meds.
Due to being in and out of hospitals as a kid, I also have severe medical anxiety..as well as getting that "i'm dying" sort of doom-attack feeling/panic, and obsessive thoughts, i've actually posted on here about it. So you may feel like no one can understand what you are going through, but I think some of us might have an inkling.
Another thing that has helped me weirdly enough, is just noticing that this fear reaction has gotten more predictable now, I know it will come when I experience something like this, and it actually has little to nothing to do with the experience itself, seeing the kind of "automatic" come and go nature of the fear has made it a bit easier to deal with.
"Just as a lotus does not grow out of a well-levelled soil but from the mire, in the same way the awakening mind
is not born in the hearts of disciples in whom the moisture of attachment has dried up. It grows instead in the hearts of ordinary sentient beings who possess in full the fetters of bondage." -Se Chilbu Choki Gyaltsen