What Causes Delayed Periods Post Intake Of Unwanted 72?

HI DOCTOR . last month first i had a vanigal penetration and later we had sex without condom but i didnt ejaculated inside my partner. After these my partnet took unwanted 72 within 30 hours.later she had a period but her next period is still due. It was sheduled these week but still there is no sign of period. Is there is any chances of pregnency.