Do I need anger management training?

I am generally happy and at peace with things and have a very happy marriage. My husband and I get along great, are very supportive and rarely argue. BUT occasionally, maybe once a month or so I lose my temper with someone. It is often a incompetent/rude customer service person or a stranger on the street that is nasty for no reason. I will give an example..

The other day I was walking though a set of doors in a busy area and the guy in front of my hesitated for a second while he struggled to push the door open. I miscalculated my steps and accidentally stepped on the back of his heal. I felt terrible and immediately and profusely apologized. He turned back for a moment without saying anything and then kept going through the door. I figured he didn't care. But then when we got through the door he lashed out and said "look at all the space you have now(gesturing to the open area we reached, is that enough for you?" I apologized again this time saying "I am so so sorry, really, I didn't mean it". He continued: "Oh you have all the space you want now. You don't have to step on my feet", pointing to his crappy old runners. I was just starting to get annoyed and said "I'm sorry, I've already told you that. Really, I'm sorry" but he kept going on with his comments, so that was it I lost it and said "What do you want from me! I said I was sorry 3 times!" and he taunted me some more so I walked right over and threatened to step on him again. He taunted me so I suggested he get out of there. He replied that I should get out of there and then we both parted and I finished it off with "that's right, get out of here little man".

I feel like I have lost control sometimes in these situations. I just fly off the handle when my right buttons are pressed. I feel like I could do anything although I think I would stop short of physical fighting,

What do you guys think? Am I a candidate for anger management?

In this case sounds like the other person needs anger management, it was an accident and you did apologise three times, what more could you do?
He was very rude.
I can understand why you 'lost it' with him.
Now I'm older I tend to just walk away when faced with an idiot like that (teeth grinding) its not worth the hassle of arguing with morons.

I wish I could do the same Great. I just feel compelled to battle it out. I can't stop myself. It's like once I start going down that path I lose my inhibitions and don't stop. I don't berate people, call them names, etc, that seems weak to me.

Here is another thing that happened recently. I went to the post office to pick up a package. There was a note at the cash that said "be back in 10 minutes". My husband remarked that he hates these signs because it is often an hour or more and you wind up waiting around for nothing. He wanted to leave. We had already had a busy stressful day and traffic was awful and we were running late for another appointment. Long story, but I really needed that package badly and if I didn't get it that day it would be returned to sender and I would wind up losing a lot of money. We waited for about 5 minutes and I was worried my husband would insist we leave. The computer was on and signed in. The store room door was slightly open and a light on so I went behind the counter and knocked on the door a few times figuring someone was in there. I know this is bad but I suppose I justified it because I thought how incredibly unprofessional the whole thing was. A few minutes passed and this woman came towards the desk angry and yelling at me "You shouldn't be back there. Get out!" Figuring it was the attendant I instinctively yelled back "Yah, well you should!" "I was on a break!" she said. "Exactly, and you shouldn't be!" I told her. "I'm allowed to take breaks" she said. We were really getting into it. Anyway, we both kept on for a while and in the end she wouldn't give me my package because she wasn't happy with my id. We left pretty pissed off but I let her get the last word in: "Have a good day hun!"

In this example I am not innocent. Clearly I did wrong. She did too. She didn't need to approach me like that. Still, there are some people, like my husband, who just never do battle with people. He has no desire whatsoever and always walks away. I will never roll over on my back and show my belly, except when I used to work I had to do this sometimes when someone would attack me. So I CAN stand down when I know I something is at stake. But it makes me feel awful afterwards. I was the scapegoat growing up and to survive I learned to fight back, not shrink or cower. I think that saved me from being walked all over at that time but I no longer need it. I think I have repressed anger from being the scapegoat.

I live in the busiest part of a pretty large city so my chances of encountering jerks is high simply because of the huge volume of people I encounter and also because of city-anonymity. I need to learn to stand down but I can't. My anger and desire to fight back is so deep and ingrained. I don't even know what happened until it is over. It is like some other force takes over.

Any suggestions on how I can change the way I feel deep down? How can I not let people get to me over petty things?

I think I have repressed anger from being the scapegoat.

That would explain it you're angry determined NOT to be scapegoat again.

Like I say as I've got older I find I've got more control over a situation by not losing my temper, instead I aim to look calm, confident and sooo reasonable (smug) that really annoys them.

I made a big effort to raise my self esteem, to make myself feel more secure. I imagine insults or complaints are like drops of water rolling off a ducks back.
Most of the time I do not get angry, Its too much effort.

I think you are right. I am close to 50 and I find that although I am improving this is something I will never escape. Did you ever react like me?

Yes I have reacted like that and I'm nearly 60. I feel angry I was a scapegoat too. I have spent much of my life pleasing others being a doormat like mother taught me to be.
The last time I lost it was at my doctors (long story) I got arrested. I spent the whole day in a cell,
crazy.
Now I hate anyone telling me what to do, I think that's why I've chosen to be single for a while. My last partner started telling me what to wear;
Skirts not trousers, straight hair not curly, then we had to watch what he wanted on TV all the time which was mostly westerns (his dream was to be a real life cowboy on a ranch in the wild west)

He turned out to be a high functioning psychopath. Sigh. I know how to pick um. So given up for now.

Now I try to be reasonable and calm.