AF due Sept 2-3 and just got a BFN 😭😭😭

I honestly don't know how many days past ovulation I am, but I just couldn't resist taking a test because of the various things I've been dealing with. For the last week I've been having brown discharge off and on (only when I wiped), my back has been killing me, and I've been having cramping off and on. Today I started feeling a little nauseous, my one breast hurts (I don't understand why it's just the right one), and got dizzy a few times. I'm just so confused!! Am I just testing too early??