Personality Disorders Support Group
Personality disorders form a class of mental disorders that are characterized by long-lasting rigid patterns of thought and behaviour. Personality disorders are seen by the American Psychiatric Association as an enduring pattern of inner experience and behavior that deviates markedly from the expectations of the culture of the individual who exhibits it.
It sounds normal for BPD to me. BPD and Bipolar Disorder share a lot of common traits, and the manic episode can fall under 'mood swing' in the DSM-IV.
There is so much overlap. Even my pdoc hasn't come down hard and fast with me, leaving my diagnosis open to both BPD and bipolar...he's not forced to "label", since he doesn't take insurance! Ouch!