Pregnancy cocktail: Femara - Estradiol - Progesterone

My doc says it looks like I have mild PCOS, but all tests indicate I ovulate on my own and I do have somewhat irregular periods, with cycles ranging from 30-40 days long. Doc has decided to put me on what she calls a "pregnancy cocktail" - Femara, Estradiol, Progesterone. Has anyone had success with that combination of pills? This is my first cycle taking it...is there anything I should expect from taking these pills? Side effects, etc? While on the progesterone this cycle I had a positive opk on cycle day 14 & 15 and had light bleeding on cycle day 19-21 for some reason...has anyone experienced this before? I was told that I should not be bleeding while taking the progesterone and yet I had a very light flow from day 19-21. Any feedback would be very helpful, Thanks!