Oh my goodness - so you didn't get teased relentlessly through school for that? Hellish! How awful for you, especially at 15.

I think your anger coming out in dreams is that you haven't had enough practice yet of doing something with that anger and how you deal with it. Anger, when not allowed to come out, can turn to shame, and more anger and frustration and on it goes! But it does seem that you've started figuring it out and at least labelling the anger, which is a good thing! Better than just exploding - but sometimes you need to, just to get it off your chest so it doesn't fester into something else!