Ashlea: great posts some excellent advice there.
Kobeh: I'm another who had a "surprise" first baby after only being with my partner for a few months. That was 14 years ago! What ever path you take there will be support and options. No need to be crippled by fear. You have had a short while to get used to the idea... give your partner a while to digest it. His first reaction will reflect his shock.

Keep communicating! People cope with stress better if they feel heard.