Periods more painful & heavy since having a baby!

I had a baby 9 months ago and since my periods returned they are so much more painful and heavy than they were before I had a baby. Don’t get me wrong I have always had heavy periods but this is a whole new level. It makes me feel so unwell. The first 2 days I actually cannot function which is not like me.

Is there a reason for this? Is it normal after having a baby?