1. Occipital Headaches
If the patient relates a recent onset of headaches, or a change in character of the headaches, the emergency physician should be alert to possible organic pathology. The emergency physician can be reassured that organic causes of headache occur...
http://www.usdoctor.com/sym2.htm

2. Chronic Tension Headache Pain Disrupts Patients' Lives
Tension headache sufferers have bilateral pain in the head and neck. The findings suggest chronic tension headaches, which affect two to three percent of the nation's population, are more debilitating than researchers previously thought, Holroyd...
http://www.docguide.com/dg.nsf/PrintPrint/35F38A15201A211385256632004AEBF0

3. Migraine: Headache: Merck Manual Professional
The pain can be bilateral or unilateral, most often in a frontotemporal distribution, and is described as aching, squeezing, or sometimes throbbing. Common diagnostic errors include not realizing that migraine often causes bilateral pain and is...
http://www.merck.com/mmpe/sec16/ch216/ch216d.html