How did you get that drunk on 2 1/2 drinks? Are you on medication or something. Do you never drink? I'm worried that you were slipped something somewhere. especially if they weren't strong. What were you drinking? Seriously?
FWIW, I think you did all you could do with this one.
You are totally being WAY too hard on yourself. It sounds like the asthma stuff was nothing even in your control regardless of the drinks. And seriously who hasn't had a few cocktails and said something silly. This is what people in relationships do. They take care of each other. It's not like you said awful things to him or about him. I'm sure there will be some point in the relationship where you will be able to return the favor (whether it's related to drinking or not). I think thanking him and letting him know how much you enjoyed the trip is totally appropriate.
I vomited on H's face once in my sleep from drinking too much cheap wine. He's forgiven me and moved on, you will be fine. Although, a well timed BJ never hurts.
We all get drunk and stupid, if your BF can't handle you during your drunk stupidness, then you don't want to be with him. But, bring your inhaler with you from now on.
2.5 decent size drinks made with tequila would do me in and I can handle my liquor. Don't sweat it. If he is really in it for the long haul then this probably isn't the worst he will see of you. If he dealt with it ok and accepted you apology, take it as a sign that he's a good dude, move on and maybe laugh at it later... nbd.
I was waiting for the part where you were making out with someone else or screaming obscenities at people, with the way you made it sound at first. lol