Could I be pregnant if have a negative pregnancy test 1 day after period due however symptoms?

While a negative pregnancy test one day after your missed period does not guarantee you are not pregnant, it is unlikely you are. Early pregnancy symptoms can be caused by a variety of factors, including hormonal fluctuations, stress, and certain medications. If you continue to experience symptoms and have concerns about your pregnancy status, it is recommended that you repeat the pregnancy test or consult with a healthcare professional for further evaluation.