1 month &3 weeks no period. a week ago i got some dark brown discharge then later that day some spotting after that days later light pink discharge ?

Go ahead & take: a home pregnancy test. Reasons for missed/late periods: low body weight, obesity, marked weight ^ or v, over-exercise, endurance athletics, breast-feeding, ^ stress, illness, eating disorders (bulimia or anorexia), anovulatory cycle (no egg released), travel, hormone irregularities, drug use, meds (i.e., birth control) or medical problems (i.e. PCOS). #1 reason is pregnancy.