Long lasting periods?

I was placed on Nexplanon on 11/3/2014 (or 3/11/2014). I knew irregular periods would happen but I got put on a pill and it helped but I just had headaches. Now that im not on the pill either I have been bleeding since the 4th oct 2015. The bleeding is not the issue.. The issue is how expensive it is... What can I do to stop the bleeding so often?