Could it be the yeast in what you're eating? I get like that anytime I eat yeast. It is in a lot of foods, crackers, soups, sauces, pretzels, chips, etc. so you need to read all the labels. I can't eat yeast or I feel sick for a day or two. As well, when I eliminate sugars and grains for awhile I feel much better. I have had to go on an antifungal diet, close to SCD, but more limiting to get well again. Maybe try eliminating yeast and see if that helps. By the way, your symptoms sound just like mine did. I discovered I had a fungus. Doesn't come up on any test. By going on the antifungal diet, I got a whole lot better. Good luck!