I would definitely think that the combo is possible... similar to pairing either with any other illness. Asthma, diabetes, arthritis, well, the list could go on and on. It's a nasty combination in one sense, but.. aside from the inflamation aspect, both have similar symptomology... so if one adapts/aclimates to one, pretty much covers the other. AND, altho it's probably little comfort to you right now, there are other, 'worse' illnesses, etc., that it could be paired with.. so in that light, maybe in time the combo won't seem so bad. And, it's possible that, given further investigation, your GI will rule it out, or bring one or both under control. If you haven't already, start a daily journal/diary.. track your foods, your meds (dose/time/anything accompanying them).. track your moods AND physical activities.. pains/fevers/chills.. Investigate everything that goes into your body.. foodstuff (check nutritional info), meds (check contents, fillers, any interactions or advisories).. beverages.. supplements, vitamins, you name it.
you could be dealing with emotional triggers, or you could be exposed to some environmental triggers... but you could be making things worse unwittingly by some of the by-products, add-ins, natural or OTC remedies, or even in some of the content of your meds. Like, (and this is a stretch, it happened to me, but it might be totally different for you).. I'm sensitive to lactose. Thought I had it in the bag, right? Just avoid dairy products, switch to non lactose ones. But the darned stuff is hidden in all kinds of things... margarine, vitamins, prescription meds.. orange juice... Welllll, once I really got a handle on it, and avoided it like the plague, my 'mystery' flares literally dropped off the scope. You really need to play detective, track N examine everything ... and come up with the 'safe' Vs 'bad' list of things that hopefully will help you bring it under control. If it is an IBS side issue, my understanding that emotional upheaval plays a part, but food items do too... but it (I could be wrong) is more immediate than in the case of IBD. Whether that's psychological or physiological, I really don't know.