Had already had it. I knew there was no way I could miss work the following week so I took 2 amoxicillinin on Saturday and 1 amoxicillinin on Sunday. My fiancé and I had sex twice before I took the amoxicillinin on Saturday and we had sex once on Sunday. IT didn't occur to me that I had taken a prescription and mixed it with birth control until Sunday night when it was too late. Even though I'm on the pill I never let my fiance finish in me. Last Sunday I had just started week 2 of my pills in my pack. I was panicking to the point of tears. I took plan B on Monday morning to ease my nerves. My fiancé and I had sex Wednesday and Saturday this past week. Again he never finishes in me. I just read to Use a backup birth control 7 days after you take prescriptions. I haven't missed a pill in this pack and I've taken them like I was supposed to. Do you think I'm pregnant or there's a chance that I am? I am suppose to start my period the week after next