IBS may be Celiac

I was diagnosed with IBS several years ago. While Lomotil works like a charm (I'd say 90% of the time I'm not too stressed), I was wondering if medications can mask symptoms of CD when CD is the culprit. I'm thinking of eliminating gluten from my diet to see if it clears up other symptoms that won't go away (sinus problems and congestion despite no allergies or colds and acid reflux unaffected by TUMS, Pepcid AC, Nexium, Zantac, Prevacid, etc.). I also suffered from SEVERE acne at the age of 18 (only on my face, though) that was cleared up with Accutane (I'm still on it). I'm concerned it could be related because no one else in my family suffers from acne that way and I'm also afraid it might come back once I have to stop taking Accutane. I don't know why it would help but I'm desperate and I know CD manifests in different ways for each person.
My biggest concern, however, is that soon I will be returning to college. Until I get comfortable with what foods have gluten and what foods don't, I'm going to have to eat as much safe food as possible... like raw vegetables from the salad bar. I'm practically terrified that if I don't have CD, eating mostly raw vegetables (and fruits) will bring back the diarrhea. I'm also afraid to stop taking the Lomotil to see if the diet's working.
Any tips? The only other foods I know are safe to eat (at least in the dining hall where I can't read labels) are peanut butter, hard boiled eggs, and, my savior even now, my rice cooker in my dorm room (I'll be forgoing the soy sauce this time around).