AITA for making out with my best friend and now i regret it

So I (19F) made out with one of my best friends, let's call him, S(19M) and I deeply regret it. It all started with us hanging out together and there was a little touchy feely on the legs. We talked and I found out that S had liked me for longer than I thought. We ended up making out and then nothing else. We also decided to try if anything happens cause we also had some friction in the previous years, but now it's not there for me at all.

Then the problems begin... I started regretting doing this the next day and two days after that we left the two of us for a vacation. Everything was kinda awkward on my side cause I don't find S attractive at all. And the whole trip S manages to make me regret my life choices and saying anything on a whim. And when I got annoyed or upset or even showed my boundaries S looked at me so pitifully it was infuriating and it was like S didn't want to follow my boundaries.

So am I the ahole for doing what I did on a whim and regretting it? And what should I do now?