What Causes Spotting When On LoSeasonique?

I started loseasonique in November for the first time ever using birth control. I spotted about 7 days for the first three months during the time I would have been on my real period if I wasn t on birth control. I spotted/bled the week before my reminder pills and then when I took my reminder pills for the last week Of my pack, I never got my period. Could I be pregnant?