I was much the same way, I was repressing all my anger. I was internalizing and taking it out on myself or denying it existed and it came out other ways.
Releasing your pent up anger is good, but don't just explode in anger too much. It is like wildfire, the more you get angry, the more the anger will surface easier in the future.
Before you know it, you are getting angry too much.
"Be careful when you fight the monsters, lest you become one."
This is such a true saying. I started getting angry at people's tendency to just explode their emotion without any control or thought about who they were effecting. This started to anger me and I used that anger to attack anyone who was doing this. Before long I started to become the asshole, attacking people for small things which I saw connect to the larger problem.
Now of course, maybe I was right, but it really didn't matter. I was hurting genuinely good people for a small flaw in their character. I was being too negative with them. I have learned to back it off a little, but keep some of what I learned with me.
Now I can more easily get angry when need be, or give someone a taste of it back if need be, without overdoing it.
Another crucial aspect to anger is that it is unhealthy for your body, especially in spontaneous anger bursts. It is very bad, I can't stress that enough (no pun intended).
You have grown as a person and that is great, but learn now to keep that anger in control. Use it as a guide to show you when you need to react more strongly and control it. Someone flying off the hook is nowhere near as convincing and scary as someone who is controlling that deep anger and has that super serious look on their face.
It is like the point right before you explode, if you can stay right there when you get angry and not explode, but release the anger on those who may (unfortunately) need to hear it in a more rational way, you will be so much better off.
You have been spending your life withholding that anger because you don't want to make people feel bad, but some people are not that responsible with their emotions. You will know when you need to act on your anger now, and you don't have to explode it, just keep it under the surface like a pot boiling, and try your best not to let it boil over into rage.