Plan B pill and pregnancy

Ch

Hey guys

So a week ago I lost my virginity to my boyfriend, we used a condom, but we weren’t sure if a little bit of cum went into my vagina so I took the plan B pill. I was supposed to get my period on the 25 of May but I got it a week early, it was very light and it only lasted for two days. Should I be worried? I’m very confused, is this a normal side effect? Should I take a pregnancy test?