What Is The Treatment For The Cut Skin On The Leg?

Hello, I'm 20. A week ago I cut myself while shaving the back of my leg and accidentally cut off a thick long piece of my skin. I cleaned and bandaged it, but it is not healing right. The skin around it is black and healed with my skin and now it's under my skin with the rest of my skin just hanging. I'm not able to get to the hospital right now. What do I do??