Norethindrone

I’m going to try to make this as short as possible. I’ve been taking this BC for a week exactly. I was spotting 14 days before I started it (first bleed after having my 1 year old). It was proscribed to me to stop the bleeding and here it is 7 days later and I’m still bleeding but it’s heavier and the cramps hurt like hell along with occasional clots (a little larger than normal). Normally I wouldn’t be on BC because I have PCOS and feel like if pregnancy happens it happens, but I only took this because my dr said it would stop it. Is this normal