Second: Rarely, if ever, is an individual diagnosed with Borderline Personality Disorder only. I haven't heard or read of this type of situation.
Third: I recommend you contact/make an appointment with a Licensed Psychologist (Ph.D. or Psy.D.) and/or Psychiatrist (MD). to obtain information regarding the possibility of a diagnosis of BiPolar Disorder or/and Borderline Personality Disorder. Note: a psychologist engages in 45-50 minute talk therapist; most psychiatrists engage in prescribing medication with very little or any talk therapy except update of symptoms (approximately 15 minutes).