When you tested negative for Celiac was that a blood test or biopsy? (Blood test is not accuate). Have you had an endoscopy? One thing I did (definitely not a cure) was get food sensitivity testing. This helped with some of the burning pain I get. As for the diarrhea, trust me I know how horrible that is. I have had chronic diarrhea for over 3 years now. Please make sure you drink water with electrolyte's. You are probably dehydrated.