Welcome to HCM! Brief answer: Pregnancy can occur if you miss the contraceptive pill Detailed answer: For effective prevention of unwanted pregnancy it requires daily administration of birth control (contraceptive) pills. Since you had an unprotected intercourse with your boy friend without taking the pill the risk of getting pregnancy increases. Further to add, as per your observation it is stated that your boy friend did not ejaculate inside your vagina it does not mean that you will not become pregnant, because the watery secretion produced by the male partner during the sexual activity but before the actual penetration and ejaculation also contains the sperms sufficient enough to cause pregnancy. Get your pregnancy test done and consult the OBSTETRICIAN & Gynaecologist accordingly.