I started my birth control this month, i was suppose to take my last active pill on Saturday sept 19 at 7pm but forgot to and i stayed at my friends house that night.. we had unprotected sex saturday night and sunday morning. I got home around 330 pm and took my last active pill and took my first placebo for the week. I am 3 days into my placebo pills and have not gotten my period yet, should I be worried?