Provera and Clomid

Tianne
I started provera on Wednesday, I have to take it for 7 days and then take Clomid CD 2-6. I have been on provera before and had AF for 21 days however it's my first time on Clomid. I am concerned that if I have AF for a prolonged time I won't ovulate or even if I do ovulate, we cant DTD as I will be on AF. Has anyone else had this problem?