I had unprotected sex and period didn't come on date..so i am afraid for pregnancy. my pregnancy test is negative.

Late period: Consider another home pregnancy test using first morning void if still no period. Reasons for missed / late period include: an anovulatory cycle in which no egg is released, marked v or ^ in weight; eating disorder; Over-exercising (endurance athletics), stress, travel, significant illnesses, oral contraceptives & other meds, Illegal drug use, breast feeding, hormone imbalances & medical problem