Chance of pregnancy, help!

This might be a stupid question but to me it’s making me paranoid. So I don’t have sex with my boyfriend but one day I was touching him and I got some precum on my fingers he didn’t ejaculate completely but I stopped before and I washed my hands and dried them maybe 15-20 minutes later he left and I rubbed myself through my underwear. Is there any chance that somehow there was sperm that didn’t get washed off and could of went inside me? Im also on bc and never miss a pill