The simple layman's answer would be - you probably have eaten an offensive food or consumed an offensive beverage.
If this continues, keep a food/beverage/medication/etc. journal. Just any notebook will suffice, keep track of everything you eat, drink, etc. After a while you'll begin to see a pattern form and know which foods to avoid in the future.
The saying - we are what we eat? It's true.
- Rectal Cancer 4/29/99, Stage I, no treatment necessary
(5 hour colon resection: 90% sigmoid removed, 15 inches of colon removed, gall bladder removed, temporary colostomy, reversed 8 weeks later)
- Chronic IBS/D symptoms, multiple bm's, on low residue diet
- Takes Colace 50 mg each evening