well first congrats!
You know this dont have to be a bad thing, you have to change your outlook,
Yes you are both young, but if you stick together you can work through this,
have you both told your pearents? im sure they will also help.
Your Gf is going to be scared right now and she needs you more than ever,
so be there, face up to it all, and think about this little new life your going to bring in to the world,
thats what matters now,
You will be ok, just stay strong for each other,