My period is late...

My boyfriend of 3 years and I had sex for the first time. At first we thought we should try it out because all his friends were having sex, but once we were actually doing it we stopped because we realized it's something we don't need yet and that we both just want to wait. However, he didn't cum until after he was out of me already. My period is late 5 days. Is that normal since it was my first time, or should I take a pregnancy test?