PCOS and TTC with Femera-Letrozole Question

My husband and I have been trying off and on for a little over two years now. I had to take a 6 month break from trying to try and regulate my cycles with BC because I hadn't had a period in 6 months. Recently I started seeing a fertility specialist and he prescribed me Prednisone to lower one hormone level, Provera to start a period since it's been 2 months since I've had one, and Femera-Letrozole for days 3-7 of my cycle once it starts. Has anyone had any luck with these? This is the first fertility medicine I am trying because he said this is more likely to work that Clomid. How long did it take you to conceive with Letrozole? What were the side-effects? I did take a hpt today before starting the Provera and it was a BFN:( Really looking for some insight and guidance in this area. I'm the first in my family to not conceive within a month of starting to try for a child so they are struggling to understand why I am on medication and the stress surrounding the situation.