hi. i'm usually late or early for my period. it's usually due to stress or my eating habits/exercise. if im really stressed sometimes i missed a whole month of period. but it came once i calmed down or destressed. if u're really concerned about being pregnant, please go to the doctor for a blood test instead of urine test. if not, just look out for signs of pregnancy. if there's none, look out for any changes in ur mood or diet/daily things that may cause the late period.