What endocrine pathology would cause all of these symptoms and why does this pathology produce this number of diverse responses?

A 35-year-old male, married with 3 children, has experienced headaches and palpitations of increasing frequency and severity over the past six months. He has also had periods of intense anxiety and panic attacks. His wife has noted that his face is often pale and that he sweats more, although he feels chilled. Recently, he fainted upon standing up quickly. Examination of the patient revealed a pulse rate of 112 with a BP of 160/92.

What endocrine pathology would cause all of these symptoms and why does this pathology produce this number of diverse responses?
What is causing the headaches and palpitations of the heart?
Why is the patient sweating, even though he is chilled?