I did some research and found the following:
American Headache Association:
The most common type of headache is the tension-type headache, and almost everyone will have one once in a while. They are recognized as recurrent headaches lasting minutes to days. The pain is often described as pressing or tightening and mild or moderate in severity. Tension-type headaches can be on both sides of the head and usually do not get worse with physical activity (such as walking or climbing stairs). Sufferers who have frequent tension-type headache should see a doctor to make sure they are treated appropriately.
Tension headaches are episodes of constant aching, tightness, pressure, and pain around the forehead, temples, or back of the head and neck. Symptoms usually occur on both sides of the head rather than just one side.
My experience is that tension headaches usually occur on both sides or across my forehead and are not localized to a particular spot. Where is your pain localized to?
The secret of health for both mind and body is not to mourn for the past, not to worry about the future, or not to anticipate troubles, but to live in the present moment wisely and earnestly. Buddha