Did I ejaculate inside my girlfriend?

So my girlfriend and I were virgins until today. Things got heated since we were alone and we ended up having sex with no condom on (I wasn't planning for this to happen.) I know for a fact I didn't orgasm while we had sex, but I felt my dick (pardon my language) kind of surge a little bit after the beginning. Like I said, I was a virgin up until this point, so I'm not sure if I'm just worrying about nothing or what. I mean, I didn't orgasm, I know that, and it wasn't for long, just barely a second or less. I didn't see anything dripping or see anything that seemed like sperm when I took it out, so am I just worried?