It's only been 2 weeks that you were really going out or doing well together? it's a new (very new) relationship and for most people a strong tie with a new gf or bf isn't made in a month. The news of a child is big news and I won't even begin to try to imagine what he has on his mind now. Just keep in mind it's not something to be taken lightly for him, whether he wants to continue with you or not, this is something he should not ignore. I believe he really does need to sort out a lot of stuff first.

What you can do is be patient and try to understand his situation without taking it personal. Try your hardest to imagine being a guy that has found out he is a father to a child from a former relationship and what that means, how much impact it's going to be on his life going forward. in a case like this there isn't really any reason to believe it's about you in any way, that is, that his lack of talking to you as much is about being uninterested now. He has good reason to step back from everyone and think things through. this is major.

@starrysky: I'm not sure how you picked up him being uninterested in the short post. Sounds like you assume that his statement that he's not speaking to anyone is just a line.