i think i might be.. what do i do how can i tell?

Hon, the first thing you need to do is calm down. I know you must think it's easy for me to say, but trust me. Stress is a big factor in keeping your period out of site.
Why can't you get to a Doctor?
You know honey, you really have to talk to your mom and dad. They won't kill you, i'm sure of that.
Is he your steady boyfriend?
Did you two just meet?
If your going to be sexually active, it's a good idea to get some kind of prescribed birth control.
What about planned Parenthood?
Try to relax for a little while longer, then see what happens. But if you don't see something sooner than later, your gonna have to talk to your parents.
Do you have a school counselor? Sometimes they can help with stuff like this when it comes to talking to mom and dad. I know your scared. Let me know what happens. Big hugs

Okay. I was in the same boat I was like almost positive my gf was pregnant. And acually right know I'm still wondering about this but this is a whole different boat. Anyway I was freaking out for a while and had no idea what the hell to do. But then I realized that my parents love me and I knew they would help me though a mess like that. I'm not saying I would be in trouble but with something as grown up as sex you have to accept concequences. And to addition parents will freak. They will be mad at you. But they can't hold a grundge against you. Afterall your their kid. I also learned that this is something that happened you cannot change. You can fix but if you don't do anything and don't tell a parent the situation will only get worse. And how do I know what your going through at a young age? I'm 14 and I'm going through what you are now it will be ok I promise