Period after delivery

For all of those who have had a baby, when did you get your first period after delivery? I will be 6 weeks postpartum on Thursday, and I still haven't had a normal period yet. I bled for 3 weeks or so, but no period. I'm not breastfeeding, so that's not what's holding it up. I will ask my doctor at my 6 week check on Thursday, but I thought I would check with all of you ladies as well.