Well... I guess I perhaps have a bit of a different take on mental health diagnoses than most people do. To me a mental health diagnosis is simply one person's take on how you fit into the criteria in the DSM, based on what little they know about you (which typically isn't much in comparison with a person's entire life experience.) It's sort-of akin to throwing darts to my way of thinking.

So, from my perspective, could your bipolar diagnosis be wrong? Absolutely. Plus as I understand it (I'm not real knowledgeable regarding mental health diagnosis) BPD is generally not diagnosed prior to the age of 18. And bipolar disorder & BPD are sometimes confused. Plus the two can occur together. Here are links to some articles, from PC's archives, on the subject of Bipolar disorder & BPD as well as links to DocJohn's articles on bipolar disorder, BPD & PTSD:

When Bipolar Disorder and Borderline Personality Disorder Combine | Bipolar Laid Bare

Bipolar Borderline Personality Disorder Differences Diagnosis | Bipolar Beat | Candida Fink, MD

Borderline Personality and Bipolar Differences Part II: Treatment

Bipolar Disorder: Symptoms, Types & Treatments

Borderline Personality Disorder: Symptoms & Treatments

https://psychcentral.com/disorders/ptsd/

You asked what you should do. Possibly seeing a therapist, & seeing if you can perhaps arrange for some psychological testing, may be one place to start? The treatment of choice for BPD is typically DBT I believe. Here's a link to an article on that subject:

https://psychcentral.com/lib/dialect...isorder/?all=1

Also here are links to the bipolar, BPD & PTSD quizzes here on PC:

https://psychcentral.com/quizzes/bipolar-quiz/

https://psychcentral.com/quizzes/borderline-test/

https://psychcentral.com/quizzes/ptsd-quiz/