Me F20 kissed someone drunk and I don't know if I should tell my boyfriend M24

So me and my boyfriend have been in a relationship 1 year and 8 months. Recently at uni there has been one classmate that is interested in me. At first I didnt pay attention to it but one day at the disco he was flirting with me but I was drunk, nothing happened that day we only dance together but since then things started scalating. From this moment I had tell absolutely everything to my boyfriend and he has asked me to stop engaging with this guy and here is where I made the first mistake and I reconize that I was being manipulated and I was being nahive and I let all my insecureties get the better of me and my values. I must say that I liked the attention I was getting it gave me validation and I did stupid things.

I didnt respect what my boyfriend asked me because he was feeling insecure and I didnt care and instead I defend this other guy because he was "my friend" and I let things scalate instead of closing everything at once and then one day, the last day of uni I got really really drunk with this guy but we where with some other friends, but I got bad drunk and this guy and I kissed. This happened a month ago and when it happened I felt really guilty and I am not sure if I told him but I do remember apologizing to him and telling him he is the best thing that has ever happened to me. I also remember talking about that night deeply with My boyfriend and he asking me to rebuilt trust and the relationship and since then I have cut completely contact with this guy but the gulit is still eating me alive because I don't know if I told him or not that day and I feel I need to tell him because I feel that he should be able to decide of he wants to still be with me or not but I do understand that it has past a month and that is really bad actually and I am so so afraid of losing him. I don't know what to do.

I would like to know what you guys would do in my place because I don't remember if I told him that day what has happened while drunk or if I should tell him now even thought it has been a month it has been really hard for me dealing with the general moral hangover and the shame of being really drunk with My friends and now just having this flashbacks and this gulit feeling. Am I doing things wrong completly? Do I deserve to be with him still? Because I am punishing myself really bad right now and I don't feel like it and I love him so very much

Tl/dr I kissed someone else while drunk and this guy has been a problem in my relationship and to my boyfriend. It has been a month since it happened but I just now beging to realize what happened but I do feel very guilty. I am not sure if I did confess while drunk and he forgive me because I remember a big talk but I do want to be honest if I wasnt already but I am afraid to lose him and to just not be worthy of him.