May i know what can cause my period to be late?can the hormones be shocked by having sex? thanks for answering :)

No, but: Hormones don't get "shocked" by having sex, but they certainly can get altered by a pregnancy. If you've had recent unprotected sex, do a pregnancy test. Remember, unprotected sex is overwhelmingly the most common cause of pregnancy. Why not protection against pregnancy and also std/s? Why are you putting your health at risk at such an early age? You should know better!