Hello: There can be a lot of causes and can be related with your age. If you are at least 50 years old, I would think in Giant Cell Arteritis as first option to rule out. It can present with pain and tenderness in the temple and jaw (sometimes both sides), jaw claudication, malaise, fever, visual loss and unexplained facial pain. The temporal artery can be tender, enlarged, beaded or with absent pulse. The approach can be done with some laboratory test: complete blood count, eritrocyte sedimentation rate, C reactive protein, and muscle enzimes (it can be related to polymyalgia rheumatica). Treatment can be done with steroids (prednisone). If the headache occurs when you are sleeping, and wakes you up, then Cluster Headache is another option. It presents with sharp pain in half of the head (always the same side), rhinorrea, palpebral ptosis, anisocoria (one pupil larger than the other), tearing, sweating and or blushing (all this in half of the face with pain). The diagnosis is mainly clinical, and treatment for acute attacks can be done with indometacin or oxygen by mask. I suggest consulting with a neurologist for a complete assessment and diagnosis because the temporal arteritis can cause permanent loss of vision. I hope this helps. Please let me know if you have any doubt before your appointment.