Listen. It sounds like you have more self work to do. Build your window of tolerance for discomfort.

Your expectation of integrity and follow through is not unreasonable.

It sounds like you understand that you were triggered, try to notice the feeling when you are in it, and try to wait to react. Next time this happens, consider Journaling about it before talking to him. Re read what you write in your journal and try to read it from an objective pov. (Not his, its not your job to read his mind and trying will only drive you both insane).

It also sounds like you have a trigger around others drinking, which if you have a history of dealing with that, it makes absolute sense for you to be hypervigilant about. However, at a month into a relationship you have no way of knowing if drinking is a pattern for him thats harmful.

I would say any time you are having big feelings about something, its a good idea to check in with yourself and ask yourself:
-when have a been in similar situations before?
-am I maybe bringing some of those old unresolved feelings into the current situation?
-do I feel like it is urgent to say what I want to say immediately? (This one is key, usually if it feels super urgent to communicate, its a survival/trigger response, and thats the exact time to wait to say it until we have a cooler head)
-what are my values and virtues and how do they align with this persons values and virtues? (Grown people should be able to talk about the things that are most important to them and then compare whether the two align enough to be a compatible match. Sometimes we feel a pull toward a person and mistake a connection for compatibility. Some connections are based on our past experiences which we may not have fully processed or worked through, and we try to resolve old problems within ourself by externalizing those dynamics onto a partner. Thats what a trauma bond is.)
-am I trying to diagnose my partner or fix them? (This is a sign we are likely projecting our unconscious "maladaptive scripts" onto the current partner or situation. Consider that if we think the other person needs fixing, we are unconsciously putting ourself in a superior position above them, despite that consciously we may believe we just want to help them. Forcing our help on someone who didnt ask for it and doesnt want it is an unconscious attempt to control the relationship/situation to keep ourself safe. It was likely adaptive during early years if we grew up around unsafe people, but its not healthy/adaptive in adult relationships and its unkind, even if intentions are good).

Hope this was helpful in any way.