Painkillers can play havoc with the gut. Following the knee replacement I got off of oxycodone after 3 weeks, Flexaril after 3 1/2, and Celebrex after a month. It still took another couple of weeks to begin to feel "normal." Prune juice helps (but don't overdo! 1/2 cup twice a day at the most.) Get plenty of fiber in your food (fruit, leafy greens, beans, etc. Steamed spinach is my friend.)

Good luck with all of that, juggling the pain and the normal stuff.