Chances of pregnancy?

so me and my bf were messing around. I didn’t know he was gonna but he just barely tapped near my vagina with his dick. He claims there was no Precum (BUT IDK HOW THAT WORKS) and he hadn’t ejaculated. It was a second. And he tapped like toward the folds of my vagina. I just don’t want to be pregnant. So any ideas on thenchances ? ( yes I know he should’ve had a condom, but we never had sex and didn’t discuss it so I didn’t know he was going to get near me. So don’t come at me with the safe sex thing) 💀I just need help