First love and already ruining it

So... Im gonna tell the story about my last 2 weeks...

2 weeks ago i had a party, this guy was there, i'll call him T, he has a girlfriend and i know her too, T and I used to just have small conversations, fun conversations tho, but that night we talked a lot, some of it was about the fact that we feel connected somehow, and that there has been some interest for a very long time.. It was because we were drunk that all of this just went so easily but after this night we talked online... Every day from the morning till night. We thought it would be a good idea if we would talk in real life without alcohol involved.. So we did, yesterday evening we went outside to a park and talk. Everything went so easy, i often feel anxious but last night i didn't.. So we talked, a lot, again...

I was meant to just give it closure and let him just be with his girlfriend, but i forgot that and only saw him. Then i kissed him... I feel really guilty and at the same time so relieved and calm.. I have never been in love before and for a long time i didn't feel anything at all.. I just wanna know if this feeling is 'IT' since my mental health is just recovering from uhm a lot... T's relationship was allready falling apart but I also think he's scared to really end it, maybe he is as confused as me... I want to get to know him, and discover if this is what I, we, want.. It has to be worth it, his girlfriend is a really nice girl and I absolutely dont want to hurt her and i usually also really disapprove cheating.. I just really want to feel happiness, i'm still hoping this could work..

I can't talk to anyone about this so yeah ... I just had to get this out of my mind for a second, the feeling that my feelings aren't a secret