Stomach pain isnt going. Should i do?

I was having stomach pain problem from Dec 25th.. after eating I was used to get gas and pain.. whenever gas passes i was used to feel good.. i tried gas medicines but ntng worked.. then took ibs medicines(meva sr vsl#3 and esomac 20) still didn't work.. after that doctor gave me sencil forte, Mebax.. it worked my severity of stomach pain reduced and felt mucb relief.. I have done stool test and USG abdomen.. my reports are normal.. But still I get stomach pain mostly when my stomach is empty.. stomach pain is mostly near the navel... and pain near upper abdomen as well.. right now doc told me to take Rantac.. Still I have the pain... it feels like this stomach pain has become part of my life... What can be the reason and what should I do ?