Unprotected sex, period still hasnt come, showing some signs??

I had unprotected sex with my girl 3 to 4 times, but pulled out, and she should have gotten her period on wednesday, and she still hasnt gotten it. She is on birth control for approx. a year, and she is experiencing minor breast pain and frequent urination? Is she pregnant? We are both very nervous, and i would just like some advice. Thank You.