Periods while pregnant?

Brooke • We're a happy and healthy family, with a 2yo👨‍👩‍👧, and #2 on the way! Hubby is hoping to have a boy, but I'd love another girl! May the odds be forever in your favor!💜

How common is it to still get your period after you conceive? I swear with my first I still had a period the first month even though the doctors told me it couldn't have been (I know the difference between a period and spotting, it was a 5 day period). Who has had this happen? I've been feeling nauseous and overly tired the past few days, but I just ended my period a week ago.