It makes me less angry whenever I hurt myself. But after I do it. I'm scared that others will see the scars and overreact. What should I do? I know this is bad but I think it's already a habit?

Try seeking help from friends, family and your school. This may seem scary but it will help you break the habit.

I know exactly what you mean. I find my self doing it to keep from blowing up and saying or doing stuff I'll regret. Then it's hard to stop. But when I finally do stop I look at the damage and am ashamed and afraid. I usually come up with some logical way it could have happened on accident and retell the story in my head In case I'm asked about it. But I usually hit myself or scratch myself, not sure what you do. If you can, ask for help. I wish I would have some self control by now...