I have been taking Zarah birth control for months now. I have not missed a dose and I have taken it at the same time everyday. A week ago, I just finished taking a prescription anti-viral medication called Valtrax. My last day of taking that, was a couple days before I started my period. Well, I had sex yesterday when I was on my fourth day of my period. (Menstrual cycle is averaged 3-5 days). I was on birth control (but then i don't know if the medication from earlier could cancel it out) and we used a condom. Well with us thinking he finished in the condom, the condom actually broke earlier on without us noticing and he finished inside me. I went and took Plan B within a couple hours of this happening. If I was on birth control and it was still in my system, and on my period almost finshed with it, and taking Plan B, should I be ok? Do I have a lesser chance of pregnancy? Will everything be ok?