Passing tissue?

Al

Okay so I got my IUD November 9th the day before my sons 2nd birthday. So it's been a few months, and I've been bleeding SUPER light for 10 days then yesterday I passed a piece of tissue or something that was about the size of a green bean, from the can, I say that cause it was more long than fat. Now I'm bleeding super heavy and having more cramping then before, is this normal? Could it be a sign somthing is wrong?? I've never had an IUD before so I'm not sure. I haven't been able to feel my strings because I have a tipped cervix and my doctor cut the strings to short for me to feel unless my cervix is low. And right now. It's not. I'm kind of worried it's a sign its moved or damaged something.