My Cycles Have Been Always On Point, Same Day At

My cycles have been always on point, same day at the exact time of day it will begin. This time it started a week early and a few days off. I have recently been under more stress, and my diet has been off as well. (Getting married) I am having dark brown spotting with an odor and it has be going on for over a week. I have recently began taking a probiotic in the last month, just a little extra info. Hoping you have some suggestions