Pregnancy test question. Help!

Hi, I'm 31 years old. Husband and I decided last November to start trying for number 2, but in the last 3 months we've REALLY started trying and I downloaded an app on my phone to help. I've been exercising more which could delay my period however early this week I started experiencing period symptoms but it never came. I should have started on the 27th and so I'm 3 days late. Took a pregnancy test on the 28th and it was negative but my period still isn't here. Is there a possibility it was a false negative?? Help!