Feeling Out of Control

I met a guy at work and we've been seeing each other casually for the past few weeks. Last night was different though. We were both feeling really amped up, maybe it was just too much coffee or something, but before I knew it, things got way more intense than either of us expected. It wasn't like me at all, usually I'm pretty reserved and careful with new people. But last night, I lost myself a little bit in the moment. Now I'm wondering if this is normal for people to just... go off-script so much when they're into someone? Is it okay to feel like you don't know yourself anymore around them?