Help reallt worried

Hello. So this is the basics- please no hate on the fact that I had unprotected sex, I will be getting on bc. I just want to know which would be the right one for me.

On feb 27 my boyfriend and I had unprotected sex, he did no cum inside of me and in between sex he would take his dick out a lot. Anyways he cummed on my butt and I don't think there was a way the cum dripped all the way down then up my vagina

Now this is my period history, in December I got my period on the 21st i believe

In January the 17th.

In feb the 15th.

And now in March today is the 17th and this morning I haven't gotten a period yet.

Hence my cycle is irregular I guess I should wait

I feel absolutely fine and no pregnancy symptoms my boobs have swollen up a bit as they always do before my period and I get very slight cramps that come and go or maybe not really

If I could have some positive feedback that I should wait for my period that would mean a lot I'm just super worried and don't want to stress, thank you