Im possibly pregnant for 3 months (blood test neg). i took these week three urine tests and the result was negative. is there a chance i am not prgnt?

Pregnancy unlikely: Today's home pregnancy tests are very accurate and not affected by foods, herbs, common illnesses, sexually transmitted diseases, vaginal spotting, or medications. A test gives a reliable result 3 weeks after sex (or when conception might have happened) or 1 week after missing a period. If done sooner, a negative result may be due to testing too early, such as less than 2 weeks after conception.

The pregnancy test: would be positive at 3 months out. 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.