Is there a high chance of pregnancy without penetration ?

On wednesday me and my boyfriend were messing around, I gave him a hand job so he had already finished, he decided to wipe if off and try to put it in. I'm a virgin so it dint go in, the head was only on the outside of the entrance of my vagina. We dint use a condom. Friday I took the plan b pill. I am worried that there was a chance that, even though his penis did not enter me, and his wiped off his ***, that when he tried to put it in there was some sperm around it, that could've gone all the way inside and I could've gotten pregnant yesterday since I took the pill until Friday. I'm so worried that there's a high chance that I'm pregnant .