Shit man, I'm both happy and feeling down for you. I'm 17, so I'm still a "kid", but seriously, RE-CONSIDER THE OPTIONS that everyone is giving you. You both still have school, let alone college, you really need jobs (one teenager with a job isn't going to cut it for 2 teenagers and a baby, especially in this day and age where the economy sucks more cock than the whore on the corner), and more importantly, you're both too young and have a full life ahead of you.
Shit, I have a gf, but I'm going to wait at-least until I'm 22 to even consider of having a baby-that shit takes a LOT of time to raise, pay for, etc.
...None the less, I hope that this works out for you two. Don't mean to be bashing and hating, I understand young and dumb love, because I'm apparently in that category too. But seriously, your life is going to start sucking ass. It might not at first, but the following months/years will be you, sitting alone somewhere, pondering, "How different would I be RIGHT NOW if I didn't have a baby..?". Just think man.
But if this is something that you really want to do, you and your gf both, then congrats to you guys. Hopefully you two can pull it off, even though the odds of that are slim to none.