It is possible that it could be your heart. However most of the time it is either your muscles on that side of the body doing something they shouldn't or stomach problems that you don't know you have. This is coming from a person, myself, who has had all three. They are very hard to tell apart.
I have often got minor chest pain
sensations after meals. I have a pacemaker, actually an ICD, and cardiomyopathy
with all of its problems to go with it. I've had muscle problems during the recovery from the operation right above the heart as I was not allowed the move my arm in certain ways, my center chest muscles started cramping from disuse. The muscle cramping scared me worse than the legit chest pain my heart has caused.
Doctors have trouble telling the difference between one and another. Don't expect yourself to be able to tell the difference. Have it checked out if you can, and chances are it will be nothing.