Why Am I Still Spotting With Brown, Foul-smelling Discharge After 7 Days On Duphaston And Folic Acid During Early Pregnancy?

Hi, I tested positive for pregnancy and to continues spotting I experienced, the doctor prescribed duphaston and folic acid. I ve been on it for 7day and the slight bleeding hasn t stopped and I also started seeing brownish discharge which smells bad. What could be the reason for this?