In such a case, I think I would say:

Ça m’apprendra à boire trois bouteilles de champagne.

You are totally correct. In such contexts, using this formulation is ironical nearly all the time. Or, at least, I never heard anyone using it the other way around, or at least not with the "ça m’apprendra" formulation.

And you are also correct for the side note. If it was someone else who drunk all those champagne bottles, you could say:

Ça t’apprendra à boire trois bouteilles de champagne !

Ça lui apprendra à boire trois bouteilles de champagne !

People will understand it as "I made this mistake, that’s what I get for doing it".