If the rectum is inflamed, it can cause cramping elsewhere...signals get all screwed up, etc. After eating, it increases peristalsis, and when the colon (no matter how much involved with inflammation), throws hissy fits, normal rhythmic movement becomes chaotic.
As well, you might also have reflux...
I think you're overanalysing everything...take the Bentyl..and most definitely start the rectal meds.
I would never question symptoms like that and believe it wasn't a flare.
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