Im on birth control (have been for years) no period and i am on my 28th day. never missed a pill, always took at same time. pregnancy test was neg.

Is your period late?: Reasons for missed /late periods: low body weight, obesity, marked weight gain or loss, over-exercise such as in endurance athletes, breast-feeding, stress, illness, eating disorders (bulimia or anorexia), travel, hormone irregularities, drug use, medications (i.e., birth control) or med problem (polycystic ovary syndrome or Asherman’s syndrome. #1 reason is pregnancy. Can repeat HPT.