Lewiss - there are many degrees of bipolar - so if you trust your caregiver otherwise I'd give the diagnosis a shot.
The one way you can know bipolar over just being "up" or "perky" is that even when not called for - like in a situation where you might be justifiably depressed or upset - you cannot be anything but happy.
However if it all seems wrong (the diagnosis) - then get a second opinion! A good doctor will be very ok with that - as this is your life not getting your car fixed! There's not many diagnostics that are more important to your well being than this.
Good luck!
intersting at my intital doc visit he told me he sensed a suddel manic in me,
& blatant ADD, at end he wrote my drug perscripts
handed me concerta slip & 1 for manic
i handed back the whatever perscipt he gave me for "manic" to him and told him
i wasnt intereseted he said ok & we've been dealing strictly w/ add since...
as far as anxiety & depression it has satrted to fade as i conquer ADD but anx & dep were offshoots of ADD, which i told him & he trusted me on that