Had sex on day 9 & same day took emergency contraceptive pill & after 9 days had little spotting 4 3days & today 36th day of cycle but no period?

Plan B: Plan B is 95% effective when it's taken within the 24 hours of intercourse and 85% during first 72 hours. So as you see 5-15% of failure rate. Take a pregnancy test.

Plan B: Emergency birth control is not as effective as regular birth control, so that bleeding could have been a period or a pregnancy implanting. I always tell my patients they should check a pregnancy test 2 weeks or so after using plan B or other emergency contraceptives.