What would cause a strong pulse on the right side of your head between your ear and temple?
You have a temporal pulse in that area because the temporal artery is located there. As far as why it is a "strong" pulse, many different things influence the force of myocardial contraction. When you feel a pulse you are feeling the force of blood against arterial walls. The amount of pressure is due in large part to your blood pressure. If you have high blood pressure or hypertension, this may be the reason for the strong pulse.
Alternatively, if your blood pressure is "normal" and still feel a strong pulse, it is due to the sympathetic nervous system. The sympathetic NS is in control when you have extreme emotions like joy, fear, anger, and anxiety.