I wouldn't worry about having AIDS as you've been tested twice and both were negative.
It sounds like you have candida because of the thrush in your throat and tongue. If your blood tests for candida come back negative, don't give up, get another test maybe through a naturopathic doctor, like a saliva test, which will diagnose you.
Hypothyroid and Candida seem to occur together with many people. The coeliac symptoms may be the symptoms of candida in the bowel. I had irritable bowel syndrome and lactose intolerance very severely for many years, then I found out I had candida, got rid of it with diet and anti fungals, and now I no longer have bowel problems or lactose intolerance!