Talk to your parents about it. This is not a clinical forum. Except for one, as of this moment, your questions posted here are related to your fears of your girlfriend being pregnant. And if she's not pregnant, would you copulate again? How irresponsible!
You posting those questions here anonymously (i'm sure that is not your real name) about your intercourse with your girlfriend who's a minor, and not talking about it to your parents or to a responsible adult you know shows immaturity. And boy, you are in trouble!
Yes, this is my answer, and I hope it's not reported because this is a valid answer.
(Sorry, I could not say this in straight Tagalog.)