What Causes Delay In Periods?

I purposely skipped my period for the month of August and September.. I tried skipping again for October, but my period started about 2 days into my new pack. After my period was over I started my pack that already had two pills gone for November. I was late a few times and took my pill 1-3 hours after I was supposed to take it. I m on progesterone only pill. I started my inactive pills Monday and still haven t gotten my period and it s Thursday. . Could I be pregnant or could skipping those two months affect my period? Or could it be that i only took 19 active pills, instead of 21? I usually get my period the second or third inactive pill. I ll be on the fifth inactive pill tomorrow. I have unprotected sex with my boyfriend at least once to twice a week. I don t remember if I was late or not on the days we had sex.