Four days late

Brittney • Momma of a beautiful baby boy born December 19th 2020 ❤️❤️

So I was supposed to start my period four days ago...have been feeling nauseous for a month but when I took a few tests they all came back negative. I’m kind of scared to test again and get another negative result...I need advice on what I should do.

Update: I took another test this morning and it came back negative. My mom thinks that I should get blood work done