Digestive Problems

Hi all!  Hoping someone can clue me in from personal experience.  When I eat or drink anything, even water, I have pain in my digestive tract at that soft spot where the ribs end.  All docs say it is unrelated to cancer or cancer treatment even though it all coincides.  If I can't "put some weight back on" within a few days I'll be assigned another specialist -- gastro-intestinal.  Really, really don't want to have to set up more appointments & go through a new series of tests.  I'm taking Prilosec OTC (2nd day).  No relief yet.  Have any of you experienced anything like this?  If so, what was the cause, what was the cure?