I've been on birth control for awhile now. I got my period August 4th, and it lasted for about 3 days. I was supposed to start my new pack August 10th but i started a day late. On August 11, 15 & 16 I had unprotected sex. I missed 3 pills in a row on the 14,15 & 16. It is now the 17th and I have what I think is breakthrough bleeding. It is not heavy but the blood is quite red. I'm thinking pregnancy is still possible because maybe I am bleeding but the "fertilized egg" (if there is one) just hasn't reached my uterus yet. What do you think?