You did the right thing. Don´t have to much of an advice because I think you are going the right way, What you said its very hard to do. We can all speculate on what was the best course of action to take but it is very different to say something and to live it on the moment and act. I think part of why you have a mild stuttering instead of a severe one is because you can stand for yourself. Keep that attitude. Maybe one or two things I would change reading your experience is: 1) Do not console him afterwards. Let him feel like shit. Don´t live with the hate or angryness but is for sure not your job.Take care of you always first and don´t be selfish for that. 2) Went alone or home feel your emotions without holding back. Cry, get angry, whatever. Feeling is always good. Feeling is YOU and a very human thing to do. Keep on.