Try rest first, if that does not work consult your physician.  Many things may cause headache, but old fashion sleep, rest, or relaxation may just be the trick.  Many Americans lack R&R because of our demanding lives and stricken economy.

Nitro may reduce blood pressure, however its intended use is to ease heart pain caused by constriction (angina).  Nitroglycerin is a vasodilator, which relaxes the vasculature of the heart decreasing blood pressure.

Seroquel is a psychotropic medication given for behaviors.  Commonly administered to the elderly for  dementia associated psychosis.  Generally administered 12.5 or 25mg 3 to 4 times daily.  I believe the max daily dose is 300mg daily.  This medication may cause sedation at highest doses.  May cause patient harm if stopped abruptly.