I was misdiagnosed as Bipolar II. I am strongly Bipolar I. As a Bipolar II, I was receiving Lamictal monotherapy which did not address mania. I had a near-lethal suicide attempt while on Lamictal. After that I was correctly diagnosed as I, but it took a few more years to arrive at my effective drug mix. The doctor who misdiagnosed me as Bipolar II saw all of it: I literally walked into his office with a huge shopping bag, but he still missed the mania. His was a very dangerous misdiagnosis.

But that is an unusual story. More typically, a misdiagnosis of major depression precedes the diagnosis of BP. Good luck sorting things out.