How long does sperm usually stick around in the vagina after sex?

I’m kinda nervous I could possible be pregnant, a few days ago I got light cramps and light pinkish/brown bleeding, now I’m two days late on my period. I thinking maybe those cramp and bleeding could’ve been from implantation, but i haven’t had sex in two weeks so I’m hoping it’s just... not pregnancy. We did use condom but they’re a always that small small chance. And that’s why I wanted to know how long does sperm stay inside to reach an egg?