I've been experiencing doubts like yourself, I think it's natural as we don't like to think of ourselves as being ill, even if that thought is subconscious. My doubts have been bought about by a Social Worker repeatedly suggesting that I've made up the illness and that I've groomed the psychiatrist into making a diagnosis.
Every time I have doubts I read through all the signs and symptoms of BP and tick off which ones are applicable and I very quickly realise that yes, I fit all the criteria for having BP whether I like it or not.
Also, I have stuck with the meds, though Quetiapine tried to kill me and Depakote sent me nearly manic, Lithium has calmed me down. I notice a difference in myself to how I was before. The MH worker I spoke to recently said that if I didn't have the BP then the medication wouldn't be effective (not 100% sure how that works) so that reassured me slightly.
Like Tucson says though, everything you describe sounds like BP and I'd urge you to give the meds a shot and see how you feel after a longer period than a couple of days on them.