I wouldn't go so far as to say don't treat the patient at all; I'd be comfortable in calling this hypertensive encephalopathy.
The first line should have been the narcotic of your choice, both for the headache, and for any associated anxiety, but if the symptoms persisted after an appropriate dose without change and N/V still developed...I think treatement is warranted.
Esmolol might be the better choice, especially prehospital, just due to it's quick onset and short duration, but as long as it was remembered that reaching a "normal" BP is not the goal (25% reduction in MAP at the most) and that it doesn't need to be instantaneous...I say treat this one.
Edit: medscape has some good articles on hypertensive emergencies/encephalopathy
http://emedicine.medscape.com/article/1952052-overview#showall
http://emedicine.medscape.com/article/166129-overview