Tension Headache: This is the most common type of headache and often presents with bilateral temporal pain, which can be attributed to muscle tension. The pain is typically mild to moderate, described as a band or a squeezing sensation around the forehead, and can be exacerbated by stress.

Migraine: Although migraines are often unilateral, they can be bilateral, especially in women. The pain is usually moderate to severe, throbbing, and can be accompanied by other symptoms like photophobia, phonophobia, and nausea.
Temporal Arteritis: This condition, also known as giant cell arteritis, is an inflammation of the blood vessels in the head, especially those in the temples. It typically affects individuals over 50 years old and can cause severe, unilateral or bilateral temporal pain, jaw claudication, and visual disturbances.
Sinusitis: Inflammation or infection of the sinuses can cause facial pain, including in the temporal region, especially if the frontal or ethmoid sinuses are involved. The pain is often accompanied by nasal congestion, discharge, and facial pressure.

Temporal Arteritis (Reiterating for Emphasis): Due to its potential for causing irreversible blindness if not promptly treated, it's crucial not to miss this diagnosis. The presence of jaw claudication, visual symptoms, or a significantly elevated ESR/CRP in the context of temporal pain should raise suspicion.
Acute Angle-Closure Glaucoma: This is an ophthalmic emergency that can present with severe, unilateral or bilateral eye pain, which may be referred to the temporal region, accompanied by blurred vision, nausea, vomiting, and seeing halos around lights.
Cranial Arteritis or Other Vasculitides: Other forms of vasculitis affecting the cranial vessels can present with similar symptoms to temporal arteritis and require urgent diagnosis and treatment to prevent serious complications.

Trigeminal Neuralgia: Although typically unilateral, in rare cases, trigeminal neuralgia can cause bilateral facial pain, characterized by sudden, severe, shock-like or stabbing pain in parts of the face.
Multiple Sclerosis: In some cases, multiple sclerosis can present with facial pain, including temporal pain, due to lesions in the central nervous system affecting pain pathways.
Raeder’s Syndrome: A rare condition characterized by a combination of facial pain (often in the distribution of the trigeminal nerve), ptosis, and miosis, usually on one side but can be bilateral in rare instances.