Advice for sex regret? (One night stand)

So here’s the deal. I’m not a promiscuous person. I’m quite reserved and cautious. I’ve only ever slept with one person before and he was my best friend. I value emotional connection in sex.

The other day I went on a tinder date, I think I was boring myself and needed to step out of my comfort zone. The guy was alright. Easy to talk to, handsome face, but not the body type I’m into. However he was very into me and was very forward about it. I guess I wasn’t used to that. It wasn’t my plan to sleep with him at the beginning of the date or even at the end of the date, and I didn’t even fully decide until his dick was out and I was like “well alright”

I felt detached the whole time though, like it wasn’t really me who was doing it, but more like I was objectively conducting an experiment on myself. Just to see if I could do something unpredictable and “crazy” for once. Just to see what would happen.

Lately I have been feeling the first bits of regret/shame because I don’t know how to square what I did with how I see myself. It’s not me, but I did do that. I never want to do it again, though. And it’s not something I want people to know about me.

The sex was meh. He came in 4 minutes in one position. It sounds shallow, but I probably would regret it less if I found him hotter or if the sex was better too. I’ve since cut contact.

Have any of you had an experience like this or words of advice? I’m just not really sure what to do with myself.