teen pregnancy

I'm 15 and my boyfriend and I have sex a lot. We have used condoms but he prefers the pull out method. Recently it didn't work so well and I just got off of my period. Since then I have been very scared. My boobs have been tender for the past week or two. I've felt sick and sometimes nauseous and lately I've been peeing a lot. I am a person that can go 8 hours without peeing so now that I'm peeing every 3 it's weird. I'm not sure what to do. I'm suppose to get my period in 2 days but if I'm late or it doesn't come I really don't know what to do.