Leftover placenta??

I am 1 month pp. I had been cramping all day then about 6pm I went to the bathroom and found this in my underwear. I have never seen anything like this come out of my body. I didn’t pass anything like this when I had my son. I called the on call doctor and she was rude. She told me “unless you’re not soaking a pad within an hour I’m not concerned”. She didn’t tell me what it could be or what could have caused it. I’m scared of getting an infection from leftover placenta. 😞 Has anyone passed anything like this after giving a vaginal birth?