Missing Period

I have been on Alesse for years now. I take the pill consistently in order to miss periods. Typically, I try to have 2-3 periods a year. I just recently stopped taking the active pills in order to have a period. Actually, today is the last day of my supposed period, but I have not bled at all. Since I have been on Alesse, my periods are often extremely light, but this time, there was no blood. I did experience some cramping and other menstrual sysmptoms. I am not experiencing any early pregnancy symptoms. I am sexually active, so I realize that pregnancy is a possibility, but I take the pill very accurately, so it should be a very slim possibility. Is what I am experiencing normal, or should I be worried?