Brown/black blood

Gwen • Had my sweet rainbow baby girl on April 3, 2017! 👶🏻🚼🍼 So incredibly blessed. ❤️
I've had brown/black blood throughout my whole period. I've been on it for 9 days now and occasionally normal color blood will poke through. Is this something I should bring up to my doctor? My last couple periods have been like this except for it being lengthy.