Could have been a uterine cast, they happen when you have too much progesterone in your system, I think it is. Ask your doctor, for sure.
I had the exact same before I fell pregnant but I didn't know I was pregnant then and I just thought I was having a really heavy period and the same came out, sorry for your loss I would book a appointment with your gp.
That looks like a possible miscarriage.
Hi hun. I would say make an appointment with your OB. I think you had a miscarriage and didn't even know you were pregnant. When I had a miscarriage at 6week it looked quite similar. Sorry for your loss, go get it checked out. Keep the photo to show the Dr. You will then need to have an internal U/S to make sure everything is out. Good luck***
Picture is in my profile because I don't know how to upload it.