Hello dear Understand your concern Yes pregnancy is possible through pre-ejacultory fluid as it contain sperm. Generally Nordette is used for regular contraception for 21 days. But in emergencies it can be used as emergency contraception pill. as you used. Take 4 pill with in 72 hour and another 4 after 12 hours. But chance of hormonal imbalance and menstrual irregularity high compares to I pill. And also note, no one contraception is 100 percent effective. So if your period will delay by 10-12 days from normal expected period date then you have to go for pregnancy confirmation by HPT/Blood HCG. If intrauterine pregnancy will be confirmed then still you can terinate the pregnancy by using abortion pill after getting advice from gyanecologist. Hope this may help you Best regards Dr. Sagar