Multiple Sclerosis (MS): This condition is characterized by demyelination of nerve fibers in the central nervous system, which can lead to a wide range of neurological symptoms, including pressure or pain in the head and tingling or numbness in the legs. The unpredictable nature of MS and its potential to affect various parts of the body make it a plausible diagnosis for these symptoms.

Migraine: Migraines can cause pressure or pain in the head, and some individuals may experience neurological symptoms such as tingling or numbness in the extremities, including the legs, during or before the headache phase.
Peripheral Neuropathy: Conditions affecting the peripheral nerves, such as diabetes or vitamin deficiencies, can lead to tingling sensations in the legs. While less directly related to head pressure, some forms of neuropathy might have associated headaches.
Anxiety or Stress: High levels of anxiety or stress can manifest physically, including feelings of pressure in the head and tingling sensations in the extremities due to hyperventilation or muscle tension.

Subarachnoid Hemorrhage: Although less common, a sudden, severe headache (often described as "the worst headache" ever experienced) can be accompanied by neurological deficits, including tingling or numbness in the legs, due to bleeding into the space surrounding the brain.
Spinal Cord Compression: Conditions such as a herniated disk, tumor, or abscess can compress the spinal cord, leading to a variety of symptoms including pain or pressure in the head (due to referred pain or increased intracranial pressure) and tingling or numbness in the legs.
Transient Ischemic Attack (TIA) or Stroke: While more commonly associated with sudden weakness or paralysis, some individuals may experience tingling or numbness in the legs and headache due to decreased blood flow to parts of the brain or spinal cord.

Neurosyphilis: A late manifestation of syphilis infection, neurosyphilis can cause a wide range of neurological symptoms, including headaches and tingling or numbness in the extremities.
Vitamin B12 Deficiency: Severe deficiency can lead to subacute combined degeneration of the spinal cord, causing symptoms such as numbness or tingling in the legs, and less commonly, headaches.
Lyme Disease: In its later stages, Lyme disease can cause neurological symptoms, including meningitis (which might cause head pressure) and radiculopathy or neuropathy (leading to tingling sensations in the legs).