First period with iud

N

So I got the kyleena iud. I'm on my first period with it and it's wild. For 7 days I was lightly bleeding and cramping, it was really bad on the first day. I was in so much pain I thought I would have to go to the hospital. I couldn't move, my legs and pelvic area was numb. I stayed up all night crying. Now I'm on the 9th day and it's heavy like my period without the IUD.

What is going on?