Stomach Ache

My husband has had a stomach ache since Sunday. We can't figure out what he ate or if that is even the problem. I made home made whole pea soup and he ate that for days and it didn't bother him. He has always had a very sensitive stomach. Today we will have some cream of chicken soup for lunch. Maybe that will help. I guess I will have to get to the store and get some Pepto Bismol as we have run out of the liquid and the pills don't see to help like the liquid.