Bf tried to kiss another girl in front of me😳

I was out with my boyfriend and we were in the line for a club and we were both high. This girl behind us had a male inflatable doll and was trying to make my boyfriend kiss it and it was funny but then my boyfriend was like “no but I’ll kiss you” to her and then went in and kissed her on the cheek😨 i left the line with him and was talking about it and basically he’s from a different culture so he didn’t want her to think he was gay idk he was just trying to prove that he’s straight bc he’s dumb (this makes him sound homophobic but he’s not he just doesn’t want people to think he’s gay🤷🏻‍♀️🤷🏻‍♀️🤷🏻‍♀️) but I was so upset and he said sorry and understood and then we had a long deep convo about cheating and about how neither of us would ever. Then the next day when we were sober I brought it up again and he still tried to justify himself but i think he was just trying to explain why I shouldn’t be upset by it. Idk do you think what he did was even that bad? should I talk about it with him more? I’m also quite a jealous girlfriend and I just can’t stop thinking about it even tho i know he definitely really loves me and I’m pretty sure he wouldn’t cheat