What Causes Brown Vaginal Bleeding On Taking I Pill Post Unprotected Sex?

28 February, i had unprotected sex with my girl friend.After that my grlfrnd ate golgappa with tamarind ( tetul) water...then she took i pill within 5 mints....after a week she feeling some bleeding with some reddish (some thing like that) .. continue for 3days .. so that now my ques is 1) she is pregnant ? 2) ipill will not working for tamarind water? plzz help me.. 3) what should she do now for unwanted pregnancy ?