I think it would be a good idea to talk to a counselor, but it's up to you. They're more likely to understand what you're going through and they can give you some advice for not acting on self harm urges, finding healthy outlets for anger, and dealing with deeper issues like the anxiety you described. It's important to learn other ways of coping instead of hurting yourself because self harm can become addictive and although it makes you
feel better, it isn't actually solving any of your problems. If you decide to tell a friend or family member, they may have trouble understanding why you self harm. A lot of people don't understand how it helps and it can be scary and worrisome to hear that someone you care about is injuring themselves. I would suggest maybe sending them a link that explains self harm or printing something out. Here's just
one example of a site that may help. Reaching out for help can make such a difference and I'm glad you're willing to get help and talk about it.