I can't believe that I'm self harming again after been clean for 5 years.
I'm sorry to hear that. Why have you started harming yourself again?
I don't know, I feel like I'm angry at my life and at the world.
Because you are self harming, you should seek immediate help. Self harming only tends to get worse and escalate so it is best to do something about it and stop now before you do permanent damage.
I'm not going to get help. In fact I am going to make a cut deeper so that I can feel the pain even more.
Cutting yourself even deeper is only going to make things worse. It seems like you aren't going to be able to handle this relapse yourself, so I really think you should talk to a professional who can help you.