Bleeding - PP or Birth control?

Snowbride02

So I had a baby 12 weeks ago.  I started taking the minipill about 6 weeks ago.  Since starting the minipill, I've had a period every other week.  I took the same birth control when I had my first kid and didn't have a period until she was 6 months old.  So I'm wondering if the pill is causing this or if this is normal PP stuff.  I don't want to keep taking the mini pill if I'm going to get a period every other week.  Any body have a similar experience?