i had postinor 2 after few hours of unprotected sex and i was bleeding on the 7th day and onwards with pains please tell me why and is it a syptom that the BP has worked?

Hi,I need a help here,my girlfriend having her period on 31st august 2013 and end it on 4th September 2013. On 5th September,we had a protected sex and I EJACULATED INSIDE HER VAGINA BUT STILL IN THE CONDOM. For safety measure,she took postinor 2 but only A PILL,NOT TWO. On 9th September,WE had a protected sex again but this time I ejaculated OUTSIDE and she did not take postinor 2. On 10th September,she had a vaginal bleeding or maybe I could say period I'm not sure and the bleeding stop on 12th September. My questions are:

1) The bleeding is a sign of implantation bleeding or vaginal bleeding or a period?
2) Should both of us be worried whether she will get pregnant or not?
3) When she will get her next period if that bleeding is not a period?
4) Since when we should count her next cycle? On the day she end her period or the day she end the bleeding? Please reply me as soon as possible as I'm so worried of her.

thank you Rosa,

Liza,

Symptoms of Postinor 2 include, "irregular bleeding, breast tenderness and nausea". If you are experiencing heavy bleeding then please contact your doctor.

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