What Are The Side Effects Of Duphaston?

my last mens was march 3,this april i have period after 14th day but ihave minimal vaginal discharge for 2days and on the 3rd day it is spot brown in color.i consulted ob gyne and she ask me to take duphaston 2x a day for 6 days.then i will come back on sat.what will be the result if i take it? im worried.thanks