I was on nuvaring for 3 weeks and I was supposed to take it out for the 4th "period week" on Friday the 10th but I didn't take it out until Saturday the 11th at about 7:00pm then 3:00 am sunday morning my boyfriend and I had unprotected sex and he came in me. I took plan b 29hrs later so 8:00am Monday morning. I was supposed to get my period sometime from the 10th to the 17 but it's the 17th and it's not here. Is it plan b messing with my cycle or could I be pregnant?