I was in the same boat as you till this month. The last period i had was oct 10th. I went to the dr's to ask what was going on?

she told me that since i was on the pill for so long the hormone was still in my system. It was the the pill that was regulating my menstration. She told ,me that i just had to wait till my body regulated itself. I was getting the symptoms of the onset of menstration at the due dates but apparently i didnt have enough hormones in my system to actually menstrate.

Biggest factor of not menstrating is stress we are still getting over xmas etc etc and not to mention trying to fall pregnant at the same time, the body just doesnt want to know about it right now.

So the best thing for you I feel is just try and relax (hahaha i know very funny isnt it well that is what i was told) and just let your body get into its natural rythem even if it is irregular, which mine is also.

Good luck