Tension Headache: This is the most common type of headache and is often associated with tenderness in the facial, neck, and shoulder muscles due to muscle contraction and tension.

Fibromyalgia: A chronic condition characterized by widespread muscle pain, fatigue, and tender points, which can include the facial, neck, and shoulder areas.
Temporomandibular Joint (TMJ) Disorder: Disorders of the TMJ can cause pain and tenderness in the facial muscles, and may also radiate to the neck and shoulder areas.
Cervicogenic Headache: Headaches that originate from the cervical spine can cause pain and tenderness in the neck and shoulder muscles, which may also refer pain to the facial area.

Giant Cell Arteritis: An inflammatory condition that can cause severe headaches, jaw claudication, and tenderness in the facial and neck muscles. It's crucial to diagnose early to prevent complications like vision loss.
Meningitis: Inflammation of the protective membranes covering the brain and spinal cord, which can cause severe headache, neck stiffness, and facial pain. Early diagnosis is critical for effective treatment.
Subarachnoid Hemorrhage: Bleeding into the space surrounding the brain can cause a sudden, severe headache (often described as "the worst headache" ever experienced), neck stiffness, and potentially facial pain.

Polymyalgia Rheumatica: An inflammatory condition that causes muscle pain and stiffness, primarily in the neck, shoulder, and hip areas, but can also affect the facial muscles.
Dermatomyositis: A condition characterized by muscle weakness and skin rash, which can also cause tenderness in various muscle groups, including those in the face, neck, and shoulders.
Trigeminal Neuralgia: A chronic pain condition that affects the trigeminal nerve, causing intense pain in the face, which can sometimes be accompanied by tenderness in the facial muscles.