What Causes Grey Discharge While On Progesterone?

Hi Doctor, my name Viktoriya/ My story kind of dificult and complicated. I had miscarriage on 6 weeks one of my twins in one week after that i started to take progesterone till almost 10 weeks. I stopted bleeding but i had so streng discharg and i felt myself like 99 years old. So i gave up to continue take progesterone and in 3 day i have gray discharg. I have to tell you that for las 2 weeks i took progesterone in gel by vagina. Im so worring and i dont trust my current doctor. I have appointment only on friday. I dont know what to do and what to think about. Please halp me