The obvious choice is birth control. Condoms are nasty devices to be used only in unfamiliar of dangerous water, and the idea of pulling out is a joke.
I have a friend waiting on a paternity test. I would have sworn he was old enough to know better. Oddly enough, when she first got knocked up she claimed the kid wasn't his, now she's suing for child support.
You need to figure this shit out before it's too late. The two of you need to be having a serious conversation about birth control and what happens if it fails. Doing nothing means there's a pregnancy sooner or later.