I just read the whole thing too. I believe you were in the right Cerv. You did the right thing and taught your son a very important lesson. There was NO disrespect to the teacher in how he handled it. Respect goes both way. True respect is respect of the person and not the title. Being in the military we say alot, i will respect the rank, but i will not respect the person. To be a true leader you need the respect of the people for the type of person you are. Your son is well on that way.
With the teacher, the only reason you would need a "couple" days to compose yourself it to make up your excuses. It is not hard to apologize for something as simple as that. They were on their way when they said they do not remember, and if they did they are sorry. That could have been expanded upon and say, that they did not realize that they did it. If they have done any wrong it was not their intent and that they will make every effort to make it up to the child. That last part is what was missing that showed the sincerity. Maybe they don't remember it, but they needed to be humble and just take it for what it was worth. You are not degrading your integrity by apologizing for something. There are many times that i apologize for something that i did not do, but because it was one of my subordinates that did it, an apology is warranted from me. I did not prevent them from doing it. I must not have trained them well enough to not do it, so therefore some blame rests with me.
However just remember, reasoning is an excuse. If you want a reason from someone you are asking for an excuse. Too many people now seem to want to know why something happened, but will not listen to the story or reason and just say they don't want excuses. This is a misleading concept. No excuses means don't ask why. Just say you did it, sucks that it happened, change it and MOVE ON. (Sorry for the last paragraph as a rant. Has nothing to do with anything Cerv did, just an observation.)
For those that say It happened to me when i was a child and nothing is wrong with me. Sorry, there is something wrong with you. Basic human liberties is a very valuable thing. This can only be taught by you as a parent. Discipline is one thing. Consequence for action. However when it comes to physical discipline, the punishment nearly never meets the crime. I do spank, and i do hit my son's hand. However i never do it out of anger and i don't show anger when i do it. I do not want my child to bring anger and hitting together. If it is meant for discipline there should be no emotion involved. When i was "disciplined" as a child, i was hit out of anger. Anger is the root of our problem. Did i turn out bad because i was hit? No because i did learn from it. I learned what i would not do. I learned alternative ways. If you need to use an object to instill discipline, you need to look at how well disciplined you are. However i do believe that there is not one way to teach a child. One might learn more from pain, and the other might learn more from emotion. We will learn this as our children grow. Just remember, if you are going to regret it the second after you do it, or you might feel the least bit guilty about it, you have drawn past your own line that your own beliefs have drawn. We do this alot with things we say and things we do. We teach ourselves very valuable lessons. Just be receptive of this.
*Steps off soap box*