My mother has been a sufferer of bipolar for the last 22 years (i.e. ALL) of my life. As a child I remember violent mood swings and she didn't have nearly as much 'mania' as she had 'depression'.
Her mania tended to manifest itself in the form of boyfriends, having up to 3 on the go at once and swapping over every week for a new one. I can't really remember if she did the crazy shopping but she probably did as we were on benefits and in council housing my whole life. She could never hold down a job but always blamed it on various other things.
Mainly I can just remember her sleeping loads. I woke myself up, got myself dressed, fed, off to school, and when I came back she'd still be asleep. She would put thick blankets against the windows and earplugs in and never get up. Not even to use the loo.
She has varied with medication, sometimes hailing it as the be-all, end-all of success and other times throwing it away and drinking her troubles down. If she didn't sruggle with alcoholism she probably would have more success as far as medication goes.
She still to this day goes through very weird phases and has lots and LOTS of self-pity, has never once said anything's her fault and blamed it on everything else. Myself and my younger sister were taken from her when I was in my early adolescence and sis was only just 3 so we have different memories. I haven't spoken to her on the phone since I was about 17, haven't seen her in person since 16. She sends very weird e-mails that I tend to just delete without reading.
Sorry to have rambled on and on, just wanted to give you a perspective. From the way you describe things it doesn't sound to me as if you have bipolar but rather a generalized anxiety.