Ferema..provera..opinions

Ive been going to the dr for fertility treatments ive done 2 cycles of fermera/letrozole. I haven't been producing big enough folicles. So the dr proscribed me provera to start my cycle so i could start over. I have irregular periods so my period doesnt always start on its own.i had a day 12 ultrasound and i started provera a week later. I took the provera and im 10 days past the last pill. Im going to my dr for an ultrasound monday to see what's going on. But i was wondering if anyone else has taken provera an never started. Is it possible to be pregnant or what was wrong that they didnt start? I stayed active before and during taking provera. Thank you for your input. Just curious to hear other peoples stories & opinions.