Me in any public/social situation:
I am a parent. Lots of you guys don't know that because I seem quite young but I was a teen Mom, long before I ever became a Pastor, my daughter is 14 now.. so roughly the same age as a lot of you. I also work with young people that are NOW recovered self harmers. It was one of the hardest things they have ever had to do. It it might be one of the hardest things YOU ever have to do too.
I would love for you to consider talking to your Mom & Dad. Do you all live together?
Be honest, be open and tell them you are scared and want help. As some of the above people posted they might get mad, but fear is what usually what makes a parent mad. They will be scared.
After you tell them ask them to help you. Tell them you need love, support and accountability. Because we self harmers are tricky, it's sometimes nice to know that there is someone that will check in with us.
Do some reading together, have once a week family meetings to talk. Openly about what's going on in your life. If your parents aren't talkers - ask them to help you find someone that is.
Feel free to message me here, it's a tough place to be when you begin cutting but you have made the first step to your own recovery!! Very proud of you. Talk to your parents. Good luck!