Taking test

Victoria
I'm 3 days late, I took a test 12 dpo came up negative, 14dpo negative again. 
Doctors office suggests to take a test when a week late but I have test now and I kind of want to test in the morning. 
Should I? Or should I wait till 7 days late. 
I'm usually a very regular cycle person, but last month I was exactly one week late and I started that day, and now I'm 3 late.