Plan B

So today my boyfriend and I were having sex and we usually use the pull out method because I've been on birth control for the past month or so. I'm no longer on bc. My boyfriend didn't pull out in time I mean he kind of did but not 100% pullout. So we go to family planning and I took plan b. I'm just nervous that There's a chance of pregnancy. Should I take a pregnancy test? If so when? I'm only 16 and my boyfriend is 17.