no.. it shall not affect your menstrual cycle as such but changes in the hormones might cause a little alteration might be causing a little delay unless you didn't take protection and might get pregnant.. rest it's absolutely fine... don't worry... take care.. good luck..
I am sorry, but this is not a forum that is written by a doctor.
Sex will affect your menstrual cycle if you get pregnant, since if you get pregnant from the sex, you will not have a period. Otherwise, it should not change anything about your normal cycle.