Postinor is said to work better within the first 12 hours after intercourse, but no later than 72 hours. I did take one 7 to 8 hours after we had intercourse. Something went wrong so I had to take it. It was my first time taking it. How do I know if it will work ? After I took the pill , the following day, I felt nauseous the whole day, which is a side effect from the pill I m guessing. What are the chances that I might be pregnant , and how long do these side effects last ? I m super worried.