Suggest Remedy For Swelling And Burning Sensation In Knee Due To Injury

My boyfriend was working and he was kicking out carpet. He missed the carpet kicker and hit his knee on the metal part of the kicker. Now his knee is swollen to the size of a softball and he says it randomly has burning sensations in it. Right now i have his leg elivated and a ice pack on it. Gave him a couple asprins. what else do i need to do?