Ii am having cramps and back pain and my period is 13 days late and is discharging a creamy stuff and a bit sleepy everday?

A pregnancy test: Would be prudent if sexually active. 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 medical problems. Pregnancy is #1 reason.