Suggest Medications For Sunburn And Rashes Around The Shoulder

I am twelve, 5'4", 100 pounds, and have no big medical problems. I had a rash once because I was allergic to something. My skin was sunburned, and now my shoulder is dark, like really bad and burned, with white spots and I know that that is not healthy. Will it heal up and go back to normal? Do I need to buy something to make it heal? We have an Aloe Vera gel that has Lidocaine and menthol in it. I have been using it, because it says it will prevent more peeling and soothes skin. It is old though. And I need something to fix my problem, not prevent it. Please help!