TTC going on month 6 and I feel that it's not going to happen. I get positive OPK's monthly, CM monthly and my period monthly. Why has it not happened yet?  Someone suggested I get a blood test done to check my progesterone levels?  Another suggested after that get an ultra sound as I could have a blockage?  I would like to try something different next month. Maybe vitex, but that worries me. any suggestions from those that had success by switching things up?  I don't want to mess up a good thing. #confused