If the sex was unprotected then it is possible that one could be pregnant, so to be sure please take a home pregnancy test after 10 days of unprotected test. Also if you have taken emergency pill then it is a possiblity that it could have affect the period cycle, please be relaxed and do not take anymore medicines without consulting a doctor. The reason of pain could be tension or pressure, please be relaxes and you could also consult a doctor to know the exact reason. Please read: https://lovematters.in/en/resource/unplanned-pregnancy https://www.fpaindia.org/ If you would like to join in on a further discussion on this topic, join our discussion board, "Just Ask". https://lovematters.in/en/forum