Put on Dark Side Of The Moon, lay down and just enjoy.
Expressing anger through songs and through weightlifting only makes you think of your anger and it's not going to disappear when the only thing on your mind through music is anger and your motivation behind bettering yourself psychically is anger.
Put on a nice chill record, I suggest checking out Grails - The Burden Of Hope.
I'll get you started:
http://www.youtube.com/watch?v=dDfNTxw4HyQ
Maybe read a book?
Chill, life ain't that bad man. You're wearing clothes, you're eating food, you're on RapVerse. It could be worse.