Polycystic lining of Uterus??

So I found out today that I have some polycystic lining. We treated it with D&C with scope but I had no polyps at the time. But we just need to keep an eye on it. I also learned that my uterus is heart shaped too. Is this why I bleed for 11 days? Does this mean I will be prone for any cancerous cells?

Anyways I am getting a iud to help with my long periods. I do not want iron through an iv again. I am just having a hard time understanding all this tight now