I've been on prefviem (ortho tri cyclen) for around four months or so. I usually start my period on the second inactive pill but this month I will take my fourth inactive pill tonight and I still have not started my period. I take my pills consistently each day (although the time may be off by a few hours every once and awhile). I had intercourse for the first time five days ago so I'm pretty freaked out. Could this be normal?