When's the next time you see your pdoc? I'd love to see his reaction if you tell him what she said. It's always fun when you tell two professionals they see things oppositely (or at least differently). I bet it'd be even more fun when one recommended the other
Bipolar is known as the most "physical" of the "mental" illnesses. There are surefire symptoms like disrupted circadian cycles (not just sleeping, but with eating, drinking, other daily activities too), and there are a lot of similar physical abnormalities between many patients with bipolar (for example, ppl w/bipolar tend to have more hyperintensities in their brain than others. I had an MRI once and they found a few. It tends to run in families which could point to genetic (but could point to just generational trauma and various reactions on the flip side), and there are some changes in certain chemicals during episodes like noradrenaline increasing during mania and decreasing during depression (but this doesn't necessarily mean it's causing the whole of the mania/depression or is a change that happens on its own that causes the mania/depression, could be the reason those symptoms show up, could be some kind of response).
Basically, there are things they know but no one knows what to do with the things they know because they don't know enough. Also psychology/psychiatry research tends to be underfunded compared to the creation of new medications that could keep businesses going instead of actually furthering our knowledge and furthering our ability to help people (unless "people" are "pfizer")