What Causes Burning Sensation In Abdomen?

For past 5-6 weeks been experiencing burning sensation in my upper abdomen and begins usually within 1-2 hours after eating. Also, just before or at the same time the burning sensation occurs, i feel a lower back ache. Within 2-4 hours after the onset of the burning sensation and lower back ache, I have diarrea which continue for usually 24 - 48 hours. The burning sensation will travel through my intestinal tract. Just recently I had diarrea (green/lime color - I had not had any green leafy vegatables) and vomited violently, heart rate fast, no fever, but body broke in a sweat, in pain, very ill feeling and weak. I am not overweight, consider myself healthy, not a heavy drinker - 1-glass of wine with dinner, no greasy foods, no sodas, do enjoy a latte a couple of times a week. Suspected a food or drink contributing to the problem but after testing and eliminating coffee, dairy, and alcohol, the problem persists. It occurs, I am ill for a few days, then better, then it returns. A mystery.