Can you try and do a few pushups? A brisk Jog or fast walk. Do you have a set of stairs you can run up? I find this helps me blow off steam. Self Sabotage will only make us feel worse in the long run and it wont do anything to change what the "customer" did to you.
I worked in CS for a long time as well and one thing that helps me deal with these characters is to view them as mentally disabled in some regard. They have issues and do not know how to handle themselves, they yell and scream at people to try and give them some power over others. In reality they are usually pretty troubled and sad individuals that are in serious need of a hug. Sad that you were the brunt end of the stick.
I find that thinking good thoughts for them after the fact, helps make me feel better, as weird as that may sound. I try and write down on a piece of paper, why I am upset, and write down a few reasons on why I think the people acted the way they did towards me. I.E. "I am upset that customer X was yelling at me, it really was hurtful and embarrassing" "Customer X was yelling at me probably because they were really frustrated that there TV has been broken for so long and they probably have lots of other troubles in life going on, this was just the straw that broke the camels back for them. Customer X was yelling at the situation and took it out on me but it really is not about me, I know I am a hard worker and work hard to help people, I hope that Customer X feels better and that things get better for them. "
Writing out a scenario like this, really helps me, perhaps it will help you as well.