Am sorry for your issue. Is the shooting pain from your buttock down your leg? I had colitis as a teenager (had colon removed) and have since developed sacroilitiis, which is comon with inflammatory bowel disease. One of the symptoms for that is the shooting pain down the leg...that's when I'm in flare up mode. You may want to look into that. My symptoms started wtih the shooting pain and leg aches when sittting, then progressed to include lower back pain and actual joitn pain. Good luck
Ulcerative Colitis 1988, had colon removed and now jpouch
Now sufer from sacroiliitis and inflammation of piriformis muscle causing sciatica like pain during flare ups. Joints very bad...take celebrex when needed.