Hi
So I just want to ask you if you had taken any emergency contraception pill after the intercourse.
If so the periods may get delayed.
Also I want to know if you have regular cycles or not.
If so , then the periods may get delayed.
If none of the above then there may be a possibility of ovarian cyst or at times there is no problem at all.
So just relax.
Next Steps
If you are worried too much on that part see a local Gynec and get a pelvic ultrasound done.