Hello. I m Dr. Christensen. I can understand your confusion. When you have pregnancy symptoms (nipple discharge, nausea, bloating, fatigue, etc.) and you ve missed a period or two, it s surprising when your pregnancy test doesn t come up positive. However, there are other conditions that could account for this picture, such as ovarian cysts, pituitary dysfunction or thyroid disease. Amphetamines, such as Adderall, are a relatively common cause of nipple discharge, and they can disrupt your menstrual cycles, too. They re not likely to cause a false negative pregnancy test, though. (By the way, pregnancy tests -- either urine or serum -- are almost always positive within two to three days after your first skipped period if you are, indeed, pregnant. And it s highly unlikely you re pregnant if you ve had several negative urine tests and one negative serum test.) Your situation warrants further investigation. I suggest you return to your gynecologist for a more thorough evaluation. He/she will probably want to perform a pelvic exam and order a few blood tests, and you could be sent for a pelvic ultrasound. I hope that answers your question, and I hope things go well!