Period after provera

I’m hoping some one can shed some light on this subject I had missed miscarriage back in April no period for three months then bled for three weeks straight, doctor decided provera hours after first dose bleeding stopped I am now on CD3 bleeding, how long does this so called induced period last and when do I call the doctor to tell her it worked my obgyn sucks obviously left me with no information I just want to see who else has been through this or after provera what the period was like!!!