help i’m stressed

so me and my boyfriend decided to take things a step further and ended up rubbing our genitals together with no clothes on. It would’ve escalated further if there was a condom available however, I am still scared that him rubbing his penis against my vagina and it having pre-semen on it could give me pregnant. I am also on my period and this was yesterday when we did this so it would’ve been my last day. HELP ME