Cherie, I dont know if it is all to do with your c/s, cause I know sometimes my AF has been like that after having the kids. The worst one I had afterbirth pains with was Erin and I would have to take panadol before I fed her to try to help. maybe you just didn't get rid of all the lochia afterwards and now it is finally coming out? Please if it is worrying you, go and see your Dr or ob OK? and if it is nothing then there is no big deal.

ETA - Cherie, are you sure they got all the placena out?