Suggest Treatment For Dull Pain In The Stomach

Hello, I have a dull pain in my stomach which is only there right after I eat. Last week my stool was of a green color. Today it is more of a dark brown. If i don't eat a meal and just pick on cheese and crackers or bland snacks, I'm pain free. It is not on the lower right side but as I said more above and bellow my belly button. I've googled gallbladder and appendix symptoms and I don't have any of them. I'm thinking it seems more like a stomach bug; however, this week I don't have diarrhea but last week I did. Is this some form of a stomach flu? Thanks!