Late Period

My period is now 11 days late. I don't think I could be pregnant. me and my boyfriend don't use birth control but he always pulls out and we've never had an accident. I've had a time before when I didn't have a period for two months but my period is normally very regular. what should I do? should I take a test to be safe or wait a little while longer? how early can you take a pregnancy test and it be able to detect the hormones in your urine?? I'm trying to not freak out but I am 18 and trying to start college and it's going to be hard with a child.