hurt at home while on wc. who pays wc or me?

i am doctoring for sprained back(work injury). My limitations on lifting are no more then 15lbs at work.The other day at home i bent over to lift a wash basket full of wash and while lifting it i got a sharp pain in my lower back. The pain is still there but more of a heavy feeling and achy.
Can i go to my wc doctor for this or must i go to my doctor?
Thanks in PA.