Usually under 6 weeks is still considered lochia. I'd just keep an eye on it.
That said, I've never gone more than 10 months without my period, and even while I was TRIandem nursing (that's right, THREE nurslings)...I still got it back at 12 weeks PP. We always nurse around the clock, on demand, cosleep, no solids until 8ish months, etc, and I still can't pass 10 months. And mine always comes back ovulatory, right off the bat.
Me (30) DH (33) Married 12 years!
Mama to 4 in arms (ages 10, 8, 6, 3) and 11 in Heaven
Thanking God for a new little one coming our way in 2016!