He is 13, and always had this very large mole on his back. Mucking about last night it got knocked, sort of split open, and bled a lot. A neighbour who is a nurse said it was okay and put a plaster on it. This morning it has lost it's black colour and gone white ish, and stopped bleeding. It is now mis shapen, and obviously has loose skin. Should i just let it heal and see if it falls off, or get it checked now. It's not bothereing him. Thanks