My Mother Said That About Two Weeks Ago She Had

My mother said that about two weeks ago she had a bump on the top portion of her back that started out small and then got a little bigger and dried out and now is hard. It has a black appearance in the center and she won't let me put peroxide on it. She said it does not itch or hurt or anything but she does have a doctors appointment on the 24th. Should she wait til then or not.