For years and years I was diagnosed with ADHD, Major Depressive Disorder, and Anxiety. It wasn't until I was hospitalized that a doctor said "Hey, it might be bipolar."

After that I didn't want to accept the fact, so I told all my psychiatrists that I wasn't bipolar (even though every one brought it up as the primary diagnosis).

My mania looks a LOT like ADHD symptoms would, but so does my depression -- inability to concentrate, hyperactivity (in mania), inability to sleep (in mania), etc.