2mo, very smelly gas, cried in pain during latest bowel movement. it looked normal except smelly also, thick like peanut butter. should i worry?

Painful BM: Usually constipation is the most common culprit of painful BM's....or you may also have an anal fissure which is beintg expanded and stretched as you have more normal BM's even if not constipated. You may wish to have your stool cultured if the smell is putrid or otherwise, more foul than it has been in the past.

Breast feed: Continue to breastfeed even during the illness. If the baby is formula fed and has gastroenteritis switching formula to a non lactose based formula may be indicated.If there any signs of dehydration such as fewer wet diapers, dry lips, a visit to your pediatrician is suggested.