I am sure you are wheat intolerant. Is this good news? (you can regain your health) or bad? (no more wheat) !!!
Your story is exaclty like what happened to 2 of my sisters and me to a lesser extent. I had vile stomach pains, like acid indigestion, which I put down to stress. Since going wheat free no more antacids, and no more other unpleasant digestive problems!!! Also I was always puffy faced in the morning. No longer..

One of my sisters is a doctor and was always v unsympathetic to the 'intolerant but not allergic' patients. then she stopped eating wheat. Total change of heart and mind. she is now a different woman, digestively speaking. Like you she had put it all down to stress before. also like you she is drastically ill if she has even a little wheat. ( I am less hair trigger)

I think we are lucky to have realised in time. You can do damage to your insides by continuing to eat something you shouldn't. A friend has some quite serious effects of undiagnosed wheat intolerance.
My other sister has an amazing range of recipes for lovely things without wheat which I will start to try when I have lost the weight and can afford a few more carbs.
Sorry do not know of any sites about this. I just know that I am so much happier and better without the evil grass!!

Best Wishes