Hello~I am so sorry you are going through all this pain, I really am stymied as to what to do, I would suggest seeing a Naturopath, they sometimes dig deeper into the issues to get to the base of the problem more than a regular MD will.
OMG same thing happens to me when I have bad diarrhea! I almost pass out and throw up, turn pale, when I get the bad crampy kind if I ate something really bad. I asked my heart doctor about it once many years ago. I'm only 32 and had this since I was like 15. The heart doctor told me there is some kinda nerve down by the intestines or something that causes this. Im assuming from diarrhea cramps? Im unsure, but if you find out more info on this please keep me posted as well and know they you are not alone! The main thing is finding the cause of the diarrhea, maybe a food intolerance or allergy or something bc its that, which is triggering that feeling somehow. Worst feeling ever!! I'm glad someone else out there gets this too and I'm not nuts!
There's probably more to the story. If not, could be you gallbladder, pancreatitis, food intolerance, metabolic disorder, or something else. So I would ask
1. Are you losing weight?
2. Are you overweight?
3. Have you had some kind of gastric surgery?
4. Do you have other symptoms? A fever? GERD at other times? High blood pressure?
5. What medications or supplements are you taking?
I have the same issues. Been to a gastroenterologist and had upper endoscopy and colonoscope plus blood work. They told me everything looked fine and I'm just more susceptible to food poisoning and stomach viruses but this has been for years. Used to happen about once or twice a year then in the last few years it's gotten to be about 6 times a year. My body temperature drops and I shake violently. It lasts about 24 hours. But the vomitting and diarrhea are so bad I ususally sleep in the bathroom with a bucket by my head. Last year they told me they thought I had gastroparisis and put me on a special diet. Seemed like it worked for a short time but I lost about 20 lbs. It's scary when I have an episode because the body responds so violently, sometimes I find it hard to breath because the vomiting is so intense.