Should I get the morning after pill?

My boyfriend and I had unprotected sex yesterday, he's pretty sure he didn't cum inside but I'm worried that he might have slightly without realising.

My period is supposed to be due anytime soon but it's slightly late. I'm irregular but my diet hasn't been good lately and I've been under some stress...

I don't want to get the pill because of the amount of times ive had it before, but I'm scared of the chances I could become pregnant. (And my late period isn't helping 🙃)

What are your thoughts?