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Spotting could be one of the symptoms suggestive of pregnancy along with missed periods. The urine pregnancy test (UPT) kits are calibrated ones, so unless the hormone levels in urine reach a certain level, they do not show positive results. They can also show false negative results. Blood/serum HCG level estimation is accurate. UPT should always be done on early morning first urine sample as the concentration of pregnancy hormone HCG is believed to be highest in this sample. Look out for development of any other new symptoms suggestive of early pregnancy. Do not delay in visiting your doctor/gynecologist for further examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). Be in regular follow-up and monitoring of your treating doctor/gynecologist. Take adequate rest. Drink plenty of water. Maintain healthy diet and lifestyle.
Take care.