Hello, Thanks for trusting us with your health concern. Here is some information I would like to offer: 1. Ovulation occurs two weeks prior to the onset of the next period. This is the fertile period where an unprotected intercourse can cause pregnancy. Since you did not have intercourse during this period, she cannot conceive even without using any pill. 2. She consumed the emergency pill within the stipulated time interval, which offers around 90 percent protection. 3. The pill contains high doses of hormone and thus creates hormone disturbances. This can cause withdrawal bleeding and delay the next natural period. She should be experiencing the usual period. Vaginal bleeding cannot happen on its own without any cause. Please see a specialist for a proper clinical appraisal and further help. Take care.