Period starts the 1st/2nd of the month. the first 3days of this month i had light pink discharge & also dark when having sex. still no period?! why??

Some thoughts...: In a woman with regular periods, some causes of a late period include: excessive weight loss or weight gain, increased exercising, emotional stress, having an illness, traveling, medicines (like birth control pills), hormonal imbalances, etc… Seeing a doctor is a good idea if symptoms are recurring or worrisome. Pregnancy is the common cause of a missed period, if sexually active.