ow ow ow. Well, nothing for it now but to use the next two months well. Walking helps rebuild those abs, start off slow and easy, add distance, speed and stairs gradually. And how about using the time to find out what was causing pain. Get to the cause so you can do without the pain meds. There really are no pain meds that are safe for the stomach over time, and your stomach lining is probably still overly sensitive now so that even doses well within maximum might still be too much.

Best get well wishes!