Self harm usually makes me anti social, I don't know why, but it just does. I say, just if things get boring, say something random like banana or napkin. Works for me. :/
I'm not trying to say that I understand because I have never harmed myself except once which was a year ago. And I didn't do anything too bad. But, what I want to say is that even if it's hard to see your friends and have them worry about you, you should still talk to them. Distancing yourself will make them worry more and it won't help you either. Time to yourself is good, (I know I like being alone), but sometimes you get too much of yourself. Did that make sense?