Chronic Subdural Hematoma: This condition is a strong consideration given the patient's age and the mechanism of injury. Elderly individuals are more prone to subdural hematomas due to the increased space between the brain and the skull, allowing for more movement and potential bleeding. The fact that she hit her head on cement two weeks ago and is now presenting (possibly with delayed symptoms) makes this a highly plausible diagnosis.

Post-Concussive Syndrome: Symptoms such as headache, dizziness, and cognitive difficulties after a head injury could suggest post-concussive syndrome. This condition is common after significant head trauma and can present with a variety of symptoms that may not immediately appear after the injury.
Cervical Spine Injury: Given the mechanism of injury, a cervical spine injury is possible, especially if the fall involved significant force and potential whiplash or direct trauma to the neck.
Traumatic Brain Injury (TBI) - Mild to Moderate: Depending on the severity of the impact and the symptoms presented, a TBI could range from mild (concussion) to more severe forms requiring immediate medical attention.

Epidural Hematoma: Although less common than subdural hematomas in the elderly, an epidural hematoma is a medical emergency that requires immediate diagnosis and treatment. The classic presentation of a loss of consciousness followed by a lucid interval and then rapid deterioration is not always seen, making it crucial not to miss.
Subarachnoid Hemorrhage: This condition, often due to trauma, can present with sudden severe headache, vomiting, and loss of consciousness. It's critical to diagnose promptly due to its high morbidity and mortality.
Cervical Vertebral Fracture with Spinal Cord Injury: The potential for spinal cord injury exists with any significant trauma to the neck. Missing this diagnosis could result in permanent neurological damage.

Traumatic Arteriovenous Fistula: A rare but possible complication of head trauma, where an abnormal connection between arteries and veins can lead to various neurological symptoms.
Traumatic Pseudomeningocele: A condition where there is a leakage of cerebrospinal fluid (CSF) due to a tear in the dura mater, which could potentially lead to meningitis or other complications if not addressed.