What is the earliest you ever tested? probably about 4 days before AF was due.
How about the latest you have gone after AF was due before testing? With my first and only pg (resulted in a m/c), I didn't test until I was almost 7 weeks along

!! I am a teacher and it was the end of the school year ... I wasn't really focused on it. I knew I was pg before I took the test, but I'd had so many disappointments in the past, I put it off a bit longer than I would now.
Are you a POAS addict? Not really ... I've had too many BFN and hate that feeling!