I got catfished

before we met he told me how his past dates didn't go to well, and I wanted to be nice so I said "I'm sure this one will be good :)" well... he lied to me about his height... I'm 4'11 and I'm taller than him. He told me he was 5'5. He also made himself look slimmer in pictures some how, he's not big but not as slim as he was in pictures. Now, his looks aren't what bothered me,  the fact that he LIED to me did. Well, we ended up hooking up and it was really awkward... I feel so mean saying this but I couldn't feel him I had to ask "if it was in" and I didn't mean it in a rude way to make him feel horrible.. I really couldn't feel it.. it lasted (thankfully) about 2 mins and he was moaning my name the whole time...... which was really weird......this whole "date" was just weird, I don't like how he lied to me and the hook up was really bad... I'm trying to stop talking to him but he gets crazy everything I do. By crazy I mean he starts telling me he's cutting himself and that he's going to commit suicide bc of me?? I know people that have committed suicide so this scares me so much.

How can I cut him off with out him going suicide?

Edit: I know that the hook up was a bad choice., I regret it and I know it's something that probably made this whole situation worse