Hi Sorcerer, welcome to the forum, and yes what you've been doing is self injury........and I'm thinking if you had/were able to use other "healthy" ways to get rid of the emotional pain you'd be choosing them, right????
And there are plenty of different coping skills out there, it's just a matter of being able to use them, isn't it??? Which can sometimes be a lot easier said than done!!!
For now maybe you could check out this link to see if any might help just a little if there's any you haven't tried or with a lot of practice???:
http://forums.psychcentral.com/self-...-yourself.html
As for things getting better with age though...........anyone at any age can (or still) be feeling emotional pain and self harming depending on their circumstances.
One thing that may really be "in your favour" though is the diagnosis, perhaps that can help you on the road to finding some real support with what you're experiencing???
And if there are any particular things that have happened to trigger the emotional pain then maybe more closely addressing them with support???
But as well, you'll find a lot of people around here who are really understanding and supportive so please don't hesitate in posting if/when/as you need support with what's going on for you.

Alison