My 3 month old keeps pooping and won't eat. she doesn't show signs that her stomach is hurting. what could be wrong?

Hard to tell: Babies can have a soft or loose bowel movement every feeding, or a couple of times a day, and still be normal. If she's not eating, check with her doctor to find out if she is sick. What milk is she taking? Has there been any change? Any fever. Baby's don't always show obvious signs of illness, but a change in eating or sleeping should be checked out.