How To Treat Soreness And Dent On Top Of Shoulder Caused Due To A Injury?

Hi on Thursday night I miss judged the fridge and banged the top of my shoulder hard it was sore straight away and the next day was a little sore but ok it now isn t sore only to touch but there is a dent the size of a golf ball where I hit. I can lift my arm and do Palm up and down without pain