Hello - I am a senior college student, also suffering from IBS. I was diagnosed was I was 10, but it really started to get bad my freshman year of college. Over the past four years I have discovered many methods to help me get through the rough periods. Talking to your professors is definitely a great idea. Whenever I have to give a presentation I always talk to the teacher about my situation and it decreases my anxiety by ten fold. They are usually very understanding.
I would say the biggest help will be to closely monitor your diet. It's extremely hard to eat well in college when everyone always wants to order pizza and drink beer. My friends often think that I'm weird b/c I follow such a strict diet, but eventually they get used to it!
Good luck
ps - Avidan, I go to school right next store to you at Drexel!