A few days ago, I was on the last day of my period, and I was at my boyfriend's house We were messing around in bed, with our clothes off. He ejaculated on my chest, and made no contact with my vagina whatsoever. I went to take a shower a few minutes later, but didnt clean or wipe off my chest first. What's the probability of some sperm going from my chest into my vagina in the shower, causing me t o be pregnant? (I'm a virgin by the way)