Jumping to conclusions is a really bad idea.

Wait until your period is due, then run down to planned parenthood and get a free pregnancy test. If that comes out negative, I would advise sticking around for the also very free birth control and condoms that are readily available there.

Did I mention birth control and condoms are free?

You should never, ever, ever have sex without a condom for your own safety and protection.

If you are pregnant, then worry about how to tell your boyfriend and the father. I'd expect your boyfriend to not be interested in sticking around and the other guy? If he wanted to be around he would be, without a baby in the picture.

You can still go to school while you are pregnant. You can still do just about anything as a parent. It will just be much more difficult.

Symptoms dont normally (although not everyone is "normal")show up untill 5-8 weeks and maybe not even then if your lucky. I would wait untill you miss your period as .Ingi said and test.

well.first off everybody's body is different so it can show anytime.but lemme tell you,.Its gonna be hard as$ hell.ive been through it.i had my son at 16.hes a 1 year now.as for the 2 guys.i have no idea what you would do.i guess your just going to have to come clean.good luck