yes. Its better to get tested at a doc or clinics like planned parenthood. my coworker told me she took more than 10 over the counter prego tests and they all say neg. she suddenly had prego symptoms a month ago and went to her doctor. got ultrasound done and now shes 4 months prego.
There is a possibility that you are pregnant because sometimes the tests can fail. However, there are other situations like stress and other medical conditions that can cause delay in your period and cause the signs you have. It is important to repeat the test and also see a doctor as well.