left sided issue

I've been in remission for 6-7 years now using Imuran as my maintenance drug. Life has been really great.

For the last 3-4 months I just have not been feeling myself. Bit of fatigue, poor sleep, my workouts not going as well and a number of niggling injuries...just not feeling sharp. My bloodwork comes back perfect and I have no obvious GI issues though I have noticed that my stools or somewhat looser and smaller lately. Nevertheless I know my body better than my bloodwork and I sense something is wrong or coming down the track!

I've been treated by a physio for a left-sided lat muscle issue for 3 months now. It very much feels like a muscular problem and related to playing 10 rounds of golf a week for the last 6 years! But the issue has not really cleared up. Now I've never ever experienced pain as part of my bad UC flares but reading some old posts here the last days it suddenly struck me that could this left sided issue be colon related. Its just a sharp, nagging tug just under my left-rib which can sometimes extend to the left side as well.

Interested here on what people think. Like the issue does very much seem muscle-related but maybe I'm overlooking something. Can colon inflammation cause referred pain or perhaps is this an example of an IBD related arthalgia?