Welcome to healthcare magic,
Taking a single tablet of Primolut N
is not an accepted method of emergency contraception
. Although being a hormone it may effect conception but nothing is guaranteed.
There are other good & very effective methods available which can be used within 72 hours & maximum 5 days after the intercourse. I suggest you should visit a Gynecologist as soon as possible to get a prescription for the desired response.
Wish you good health.