I'm 17 and on birth control. i have not missed my pills. what can be wong?

Late period?: Have you missed your period? You don't indicate what the problem is. Missed/late period: low body wt, obesity, weight ^ or v, ^exercise, endurance athletics, breast-feeding, stress, illness, eating disorders (bulimia or anorexia), anovulatory cycle (no egg released), travel, perimenopause, just starting menstruation, hormone irregularities, drug use, meds (i.e., birth control) or med problem.