Paranoid

I know this is stupid but I guess I overthink everything lol. So I am 15 and I have been dating this boy for a little over a month and the other day we were making out and I guess you could say grinding?? We both had all of our clothes on but I wasn’t wearing underwear. After he left, my pants had something on it, very close to my vagina. Either from me or him I am not sure, but is there any way or chance I could get pregnant from grinding if his cum gets on my pants?? I know this is a stupid question and I am probably paranoid, but all heath classes say you can get pregnant without actually having sex and I am not sure if this is one of those cases.