Missed period, have firm boobs, hpt says negative. what could it be?

Retest: You may have tested too early. If you are 4-5 days past the expected date of your period, you may repeat the test, using first morning urine and follow the directions in the package carefully.

Agree w Dr. Singh: retake HPT in 1 week.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.