When I went to get DS2 (age 5) from his swimming lesson today (I don't watch) the teacher told me she'd had to tell him off an awful lot today, as he wasn't paying attention/doing as he's told.
I asked if this was usual for him and she said not at all. I thought phew, we'll treat it as a one off then (ie at least he's not devil child all the time), but she seemed to think that the fact that it was unusual for him made it worse.
I took DS2 off for his shower and had stern words with him. We agreed that when we went to collect DS1 (who was in the following lesson) he'd tell the teacher he was sorry and promise to behave better next week. Which he did. She said "that's OK then" but didn't even glance im my direction. Did I get it all wrong?
I don't see what else you could possibly have done. I think your handling of the situation was spot on - and all children have off days where they don't pay attention/are off in Laa Laa Land for whatever reason. Relax