Hi AngieB,
I also used clomid when trying to get pregnant (though it did not work for me, I moved onto injections, and had success with that). Anyway, with a low progesterone level, this does in fact mean that you did not ovulate, as progesterone rises immediately after ovulation. It is improtant that you ask your doctor to monitor your ovaries throughout the clomid process. Mine did not for the first few cycles, which basically meant that it was wasted as we really had no idea what was going on. Generally it is not recommended to do anymore than six cycles of clomid before moving on to an alternative treatment, as it is thought to increase the risk of cervical ancer in later years. Generally the dosage should be increased every cycle until ovulation is confirmed, and then that dosage would be continued until you are pregnant, or you have had six cycles (some Doctors will give more than six though). Also, if a future scan does show that you have ovulated, but your progesterone levels are still low, you can take an oral progesterone pill to boost the levels, as low progesterone levels will cause your next period to come too soon, therefore not allowing sufficient time for implantation to occur in the uterus.
One last thing, may I recommend that you read the book called 'Taking Charge of your fertility' It is an excellent resource, and I found it to be very helpful in my struggle to get pregnant. You can also visit their website at www.ovusoft.com. There is an excellent message board which is dedicated to trying to conceive, there is lots of information to be gained there, as well as much needed support by other women going through the same process.
Good luck to you.