SOS- please help

I’ve been on the pill for 5 years. Take it everyday except like once a month I forget to but take it as soon as I remember.

Anyway, I was supposed to start yesterday. But no sign of my period yet still. My bf and I have sex but he pulls out like 20 seconds before he finishes.

I had a huge exam the other day, so my stress levels are high and since I haven’t started yet, the stress is still there.

I shouldn’t be worried right? Idk. Help me out girls.