Is this possible?

Last time I had sex was probably about 5 weeks ago, I had my period from like August 28-September 4th. My period is now late tbis month is it possible I’m pregnant even though I haven’t had any sex this month? But I did have sex the day before my period started last month so I’m not sure if my period would still happen or not? It was a week long and heavy like normal so it wasn’t implantation bleeding I don’t think. But I’m late so I’m worried now lol I would take a pregnancy test but I just want to know if this is possible before I spend money on one