HELP!!

So I had sex for the first time on thanksgiving and I was suppose to get my period on the first of December and it's the 4th. I haven't told the guy I had sex with I haven't got my period because I'm usually always late.But I have been cramping like my period is about to come on. I was wondering should I take a pregnancy test to be sure I'm not pregnant or should I just wait and see will my period come? PLEASE HELP IM REALLY SCARED!! 😰