Pain in right side below chest and back.

My mom had appendicitis operation 5yrs ago, she used to get pain in the same area sometimes during that period after operation. But since few days, she is having pain in the same area and back on the right side.. Also she is unable to pass gas and having consipation problem since young. In past few days, her bowel syndrome was not scheduled proper due to family issues.. Please can you tell me that whether that pain is due to acidity or not as she thinks that its the same problem.. Also her stomach is bit seeming to be filled with gas as she is unable to pass it.. Please help my mom in this.. What is the exact reason? She also entered menopausal period few months back.. Can we get the real issue in xray or tests??