I've never had a T falling asleep during an appointment. If it would ever happen, I would want to say that I would throw a glass of water on his/her head, but I'm probably to chicken for that. I think I would yell ''wake up'', say some things like ''this is not acceptable'' and walk out.

I think you did the right thing. Though in my opinion you couldn't really do something wrong in this situation. You shouldn't have to worry about your reaction in this situation, you're pdoc should be the one to think and think about this and make sure this will never happen again.