I was to get my peroids on 2nd july on 30th i had unwanted 72 still havent got my periods home pregnancy test is negative . kindly advise ?

About Emer. Contrac.: Emergency contraception pills are hormones and can alter a woman's periods for that month and the month after. One should take a pregnancy test (follow the instructions on the package) about 3 weeks after sex. It can be hard to predict the timing of the next menstrual period that comes after taking emergency contraception hormone pills.