Childbirth often disrupts a woman's cycle and you can't predict what yours will be after by what it was before. Provera often works for this purpose, but not always (as you have seen). Hormones do fluctuate and women sometimes miss periods for no apparent reason. One thing you can depend on with the human body is that it is not always predictable. Just because it "worked" before is no guarantee it will again.
I would wait it out and see what happens over a couple of months' time. While you are trying to conceive, it just may still take a little more patience. We don't have as much control over these things as we would like to believe. Time is sometimes the cure. If not, you should consult with your doctor again.
The answers in online forums are for information only and are not intended to substitute for medical advice and care. Please see your personal health care provider for further evaluation of your individual case.
Debbie Miller, RN