Moms who exclusively breast fed: when did your period come back? I'm 4 months pp and recovering from…

Moms who exclusively breast fed: when did your period come back? I'm 4 months pp and recovering from a pelvic infection so I'm trying to figure if I'm cramping and bleeding a little from that or if my period is coming back. I got the depo shot a month and a half ago after I had an IUD taken out (it was the cause of my infection). The bleeding isn't from sex. It was only on the toilet paper when I wiped but it was more than just a little pink tint. Help?