False positive pregnancies usually have no symptoms and may have PMS. False positives can be caused by a short pregnancy, failure of the pregnancy test, incorrect testing, etc. 1. False positives may not have any symptoms and the causes are usually: (1) Short duration of pregnancy: The pregnancy test is to test the concentration of human chorionic gonadotropin (HCG) in the urine. If the duration of pregnancy is short, the level of HCG in the urine is not enough to cause the pregnancy test to be positive, so there will be false positives, and the test will only become a double bar positive in a few days’ time. (2) Failure of the pregnancy test stick: The pregnancy test stick bought is too long, has expired or the quality of the manufacturer’s production is not qualified, etc., which may lead to false-positive phenomenon. (3) Incorrect test methods: pregnancy tests include pregnancy test sticks, pregnancy test cards and pregnancy test strips, which can lead to false-positive pregnancy tests if they are not done correctly. 2. Premenstrual Syndrome: False-positive pregnancy test stick test, usually right up to the time of menstruation, or menstruation has been wrongly delayed, there may be breast swelling and pain, abdominal discomfort, short-tempered, easy to get angry and other symptoms, which can not be easily separated from the symptoms of early post-pregnancy. It is best to go to the hospital for a blood test for HCG to confirm whether you are pregnant.