When will a real period come?

Ra
I had a c section.. bleed on and off for 4 weeks, been without any bleeding for 2 weeks now. I go back to work on the 18th, I'm wondering when I'm gonna get a normal period.. I REALLY don't want it to be a surprise at work! And I honestly don't remember what happened with my first cause I breastfed and it delayed mine for awhile. I'm only doing formula this time around.