Females only! preferably a nurse or something?

ok, i gave birth 4 weeks ago and me and my husband had today (we have had before after the birth) i bled after wards, which i'm sure is normal i've bled after the other times as well, but then something that hasn't happened before happened. i found it on the floor of the bathroom when i went in there to clean up (it fell out) it was a little clump of tissue like matter, about the size of a dime, it was a little squishy but most mostly firm (like tofu?) i think it was white because it was pink with the blood on it, ummm is it like placenta or something i don't think i'm supposed to be ping that sort of thing four weeks later...