I respect how you are feeling about having doubts about your diagnosis, but to me it comes across as a rationalization on your part. This is how it is sounding to me. We BPers are quite good at this. I think this ability should be considered as a symptom of BP.

Many of us have an incredible capacity for this rationalization when it comes to our disgnosis. For some, this rationalization never goes away. Or do I call it a delusion by then?
I have had symptoms when I was in grade school. This explains allot of my behavior back then. Episodes of mania to substantial depression. As usual, I was first formally diagnosed with clinical depression. The BP diagnosis came in my 40s. So do not confuse the time of the first onset of this MI, which may be very hard to pin down, and the date the person was formally disgnosed with BP.
So personally I do not think BP just shows up during the middle of our lives. Maybe that is when it has become more problematic. As a consequence the formal diagnosis comes later too. There is always being able to get a second opinion. Still with one person, having six or seven “second opinions” still did not prevent them from doubting their diagnosis at a later time. I think this is even when they ended up in a psych ward. Several times. Each time they stopped taking their medication, not believing they have a MI.
I do think this extreme is not that uncommon. Here is a kind of litmus test. Has the person such as yourself actually considered the very real possability that the reaon they feel better is because their meds are working? There is a reason they including yourself are on meds in the first place. I guess it is the nature of the MI.
So my suggestion would be to get a second opinion. Who knows? You may be correct. Furthermore, the side effects can sometimes be worse than the problem the meds are attempting to treat. I wish you well in getting to the truth of your matter. BTW I wish I did not need these nasty meds!