I had sex the first day of my Fertility day around 7 am in the morning, and the person that I had the intercourse with did not pull out. Therefore... (we get the drift). I did not purchase the pill until that following Mondat around 2 pm due to financial issues. Tuesday I was extremely tired ( I thought due to walking in the heat) I am trying to see how effective will the drug be for me due to the fact that it was my fertile day and being so close to the 72 hour mark.