Could I be pregnant?

[Concerned_and_Confused]

So yesterday my boyfriend and I were messing around a bit. I still had my undergarments on, and he was grinding against me (his penis was out). He didn't climax, but my panties kept snagging and I think he might've accidentally penetrated me a bit. I've never had sex though, so I have no idea whether he did or not. Would I have definitely been able to tell? Also he hadn't ejaculated in awhile, so his pre-ejaculation fluid couldn't have had any sperm, right? (I'm not even sure that there was any pre-ejaculation fluid.)

I know the likelihood is not high at all, I'm just scared. I'm really young and I can't talk to my parents about this without my life turning upside down. Is there any chance at all of me getting pregnant?