What Causes Heavy And Prolonged Vaginal Bleeding While On Implanon In Arm?

i was on the depo shot first well it gave me bad leg cramps so they switch me to the implant in my arm i got that december 6th 2014 well i started my period a day after christmas and im still on it its very heavy and painful so they gace me ortho micronor said it will stop the bleeding is that truth