Hypomania is the middle ground for people with bipolar. they feel great, everything is going great for them, they are neither extremely depressed nor extremely manic (manic is when the bipolar person is making decisions with out considering the consequences, having lots of mood switching, irritable, angry, happy sad, excited....all their emotions are just going everywhere.

heres where you can read more about bipolar and its phases...
Hypomania and Mania Symptoms in Bipolar Disorder

A personality disorder is a general label that has many different personality disorders in it...kind of like dissociative disorders is a general label for all of the dissociative type disorders.

each one of the personality disorders have their own definition, diagnostic criteria and symptoms, those some may share some of the same symptoms.

example borderline personality disorder is one type of personality disorder and anti social personality disorder is another type of personality disorder but they are both listed under the general term of "personality disorders"

here is where you can read more about borderline personality disorder....

Borderline Personality Disorder Directory: Find News, Features, and Pictures Related to Borderline Personality Disorder