Stress (like in your case) often trigger abdominal issues. IBS is known to start this way. IBS is totaly undefined condition, so you might 'catch' this diagnosis from someone quite easy.
FD is also a vague diagnosis and it doesn't explain your symptoms.
Symptoms, you described may come from:
- allergy - like astmatic attack, well...
- hypoglicemia - occurs in diabetics, but also in non-diabetics. Dg: blood glucose level after exercise.
- psychic. It's like pannick attack when, parasymphatetic nerves predominate, your blood pressure falls, this causes weakness, hyperventilation...You would know for a cause in this case - some unsolved issue, or beeing psychicaly unstable.
If I get you right, you can get this attack during simple walk, and it happens on regular basis (or is it more random?) It can help, if you can make connection between exercise, eating, sleeping and symptoms.
FD = Functional Dyspepsia.
No it was not an asthma attack.
Difficulty breathing -- it's like when you have stomach cramps or someone hit you in the stomach, it would be difficult to breathe deeply and normally. I can breathe, it's just that it's like I'm sometimes so tired that I have to consciously remind myself to breathe.
Basically, my once healthy iron-cast stomach just went bonkers after the run. To me this has been a mystery.
Familial dysautonomia?
en.wikipedia.org/wiki/Familial_dysautonomia
Well, I think FD would not go with difficult breathing (if you mean a grasping or wheezing like attack).
Hyperventilation, increased heart rate, weaknes, haywire (dizziness?). With saying 'weak' you mean like weak in legs, or you mean 'nauseated'? (I guess bot, right?), difficult to breathe (this also occurs?)
My guess:
-asthmatic attack or precisely: "exercise-induced asthma" (search for this term)
I think such attack can be induced with some chemical - for diagnostic purpose.