I am 21 years female. I took ipill within 24 hours of unprotected sex (13 dec) after which I got my periods the very next day (14 dec), which continued for 6 days (till 20 dec))(usually my periods continues for max 4 days). But this month it's (25 jan) and I still didn't get my periods. I have taken pregnancy test at home (on 20 jan and 23 jan) in the morning which is negative. What should I do now?