Dear sir..i can understand your problem..In my opinion you should consult first to a physician then with his advice if he thinks go to neurologist or cardiologist . Now coming to your complaint . .you have headache dizziness and extreme fatigue.you have only mentioned that you have headache that is from left temporal to right and that is like tightness . Based on this is suggestive of more of tension headache not migraine .to diagnose tension headache you should not have nausea vomiting photophobia throbbing etc.for treatment it generally respond well to simple analgesics .various relaxation techniques techniques will help you much.for chronic headache amitriptyline is the only drug that can be given.apart form this there are few other cause as well such as refractive errors of eye ,astigmatism, ocular muscle weakness , glaucoma all these can be diagnosed very easily by ophthalmologists get your blood pressure and hemoglobin level checked .as high bp and low hemoglobin can also cause all this.there is no need of further expensive work up such as MRI etc.yiu need a good physician . How this will help .