Help with someone at school?

Okay, i umed this boy in my college cl liked me or something (I would notice he was looking at me in cl, and when I turned around to see, he would look away or down.) Things progressed. He began to get very antsy around me. He would try to avoid me and walk away from me. I tried talking to him on AIM, and he seemed a little bugged by me. I feel very uncomfortable around him now because he and his friends, I believe, are stalking me or something like that. I asked him if he wanted to be friends when I was talking to him on AIM, but he said we are not friends, aquaintances, and he told me and my creepy friends to leave him alone.