Hello..I had unprotected sex on 31st august with my gf..n she took i-pill within 24 hours... she get perids on 11 the september, her actual date was 22nd of september.. last month she was getting perids on 11th september so this month periods has to come on 11th october right..but till now she is not getting periods..so plz let me knw there is any chance of pregnancy? ?