Pains in leg and buttocks after birth

Hi i gave birth to my beautiful little girl 6 weeks ago. For the last week I have had pain in my right leg and buttock and around my lower back, it's so painful I can hardly walk and when I do I'm limping! Has anyone else had this pain and is this something I should be worrying about? 

i had an epidural that wasn't put in correctly so they had to do it again, I'm wondering if this pain has anything to do with it as the leg I have the pain in was the leg that completely went numb?

any help would be really appreciated x