Postpartum period/ breastfeeding

I am 7 weeks postpartum and just started getting what seems like a period. I am exclusively breastfeeding and was told by my OB that it was unlikely for my period to return this soon because of breastfeeding. I called the OB about the bleeding and they did not seem concerned, but were also not overly helpful in telling me if this was my period or not. Did any of you who exclusively breasted get your period back in a short amount of time?