I had sex on 28th of April (sex means may be semen touched the vagina). After 2 days I took a tablet of unwanted 72 (after 60 hr but before 72 hr) .the day after sex I also had on periods on 29th of april. I also took 13-14 home pregnancy test and all showed negative. For being extra sure I took 2 more tests on 26th of may (around 26 days after everything happened) and they too showed negative. I am having back pain which I usually have on my periods but the periods didn't came out yet My periods due date was 28th of May but it didn't came out yet (4 days delay already) Is there still any case of being pregnant? Plus what are the consequences in case unwanted 72 is taken where there was 0% chance of getting pregnant? Please help.