beezo,
thanks for the post.
You are young to have hypertension. This is why you are being evaluated for other causes. The episodic nature of your symptoms do raise the question of some type of adrenal tumor and that was why they were evaluating you for this disorder. Sometimes, we aren't able to find a discrete cause and the blood pressure is caused by your genetic disposition to the disease. Also, anxiety can certainly present in similar attacks. It is important for you to continue your follow up with your physicians who can monitor your blood pressure and response to therapy over time.
good luck