Online diagnoses tests/quizzes aren't regarded very highly by the professional medical community. They are, perhaps, infamous for being inaccurate due to a combination of factors, including their inability to take into consideration alternative explanations for symptoms.

Also, most people will score themselves incorrectly and find traits in themselves that either aren't present or don't meet a severity or level sufficient to warrant a diagnoses.

However: online quizzes are good for assistance to decide on key topics to discuss with a healthcare professional and thus can occasionally be used as a diagnostic tool. It would be good if you can do one of the quizzes that give detailed feedback and print off the summary of answers (if available) and present that to either your current pdoc/psychiatrist or approach a different one for a second opinion.

I was diagnosed with depression and anxiety myself for three years until I got the diagnoses of Bipolar Disorder, though that was based on class peers and educational staff pushing me to query Bipolar (some of my most severe Bipolar Symptoms developed during college). It may therefore be wise to collect as much evidence as possible and then present that to your psych/pdoc.

Keep a mood diary for a while, writing in it your mood and the triggers (or lack of). Explain the symptoms felt at the time of the mood. This will, with a printed copy of the Quiz and your answers to it, help during the process of a diagnoses. If its still to no avail, get a second opinion.

Try to be positive (:
RB