My stomach was hurting for one day only last week but then my stool was a green color for a few days. the only symptom i have been having now is no appetite for over a week now. i went to my primary doc, they think its a stomach flu but im not sure?

The main agent adding color to the poo is the material made by the liver called bile. It starts out a dark green and goes thru the yellows to brown depending on the influences of various factors in the intestines. Rapid transit thru the system, as may occur with diarrhea may have a greenish yellow or yellow appearance. The slower, more likely browner.