You're not an ass for doing it via IM. Your safety as an issue. You were taking care of yourself. Now you don't owe him a thing. He doesn't need to be informed of your pregnancy nor anything else. I hope you can block him so he can't keep sending you messages. is the stuff you left at his place important? If not, don't bother going there to get it. If it is, you can ask him to leave it for you in a neutral place, like at a friend's or even a Mailboxes Etc., and send someone else to pick it up, not you. Be careful.
The world opens up... when you do.
Oh, oh, can't you see? Love is the drug for me. ~Bryan Ferry
"Love is that condition in which another person's happiness is essential to your own." ~Robert Heinlein