What Causes Pain Around Ribcage?

Hello. I have been having an achy pain in my left rib cage into my back for the past couple months. I went to the doctor who initially said it sounded like a stuck rib it didn t get any better. I went back and he told me could be a hiatal hernia. Had a chest x ray that showed no sign of hernia or any fractures. I ve been taking Prilosec OTC for the last 11 days. The other night I had sharp pains in my upper left ribs when I took too deep a breath that lasted for about an hour. What could be the issue here?