Is It Normal To Have Brown Discharge, And Does This Indicate That My Period Might Start Soon While Taking Duphaston To Delay My Period?

Hi!! I am 20 years old. I am takind duphaston 3 tablets per day because i want to delay my period that is due to come at 14/04 it is normal that i have brown discharge?! Does this mean that my period while come tomorrow or the day after that?! I am taking this medicine since 08/04