On Wednesday afternoon I had an onset of strong gas, stomach cramps and a low grade fever/chills. The fever passed by Thursday am, and the cramps have lessened, but I continue to have headache, fatigue and excessive gas in the upper tract, causing the need for frequent loud bleching to relieve stomach discomfort. It is now Friday night, and I am still having pain and strong gas. Energy level is better, but still a slight headache. Are there some viral infections that could cause these symptoms? Wondering how long to let this pass on its own before I see the doctor.