Brown discharge could be anything like mixture of blood and secretions.
You must consult expert gynecologist.
Plus For the pcos my best advice would be
1. Daily exercise under fitness expert
2. Dietary modification
3. Weight reduction (if you are overweight)
Next Steps
Consult Gynecologist
Workout
Diet
Health Tips
Plenty of fluids
You can consult me for Precise advice regarding Workout & Dietary modification
wishing you Healthy recovery