Benign Paroxysmal Positional Vertigo (BPPV): This condition is characterized by brief, intense episodes of vertigo triggered by specific head movements. Given the patient's recent head trauma while working on a camper, it's plausible that the inner ear was affected, leading to BPPV. The absence of loss of consciousness (LOC) and the need for pain medication at the time of the event supports this diagnosis.

Labyrinthine Concussion: This condition can occur after a head injury and affects the inner ear, leading to vertigo, nausea, and sometimes hearing loss. The patient's recent head trauma makes this a possible diagnosis.
Vestibular Neuritis: Although less directly related to head trauma, vestibular neuritis (inflammation of the vestibular nerve) can cause severe vertigo, which might be exacerbated or triggered by the physical activity and head movement involved in working on a camper.

Subdural Hematoma or Other Intracranial Hemorrhage: Although the patient did not experience LOC at the time of the event and does not require pain medication, the possibility of a slow-growing subdural hematoma or another form of intracranial hemorrhage cannot be overlooked, especially in an elderly patient after a head injury. These conditions can present with delayed symptoms and are potentially life-threatening.
Cervical Vertebral Artery Dissection: This is a serious condition that can lead to stroke. The mechanism of injury (hitting the top of the head) could potentially involve neck movement that might lead to dissection, especially if there was significant force or if the patient has underlying vascular disease.

Perilymphatic Fistula: This is a rare condition where there is an abnormal connection (fistula) between the inner and middle ear, leading to vertigo, hearing loss, and sometimes nausea. It can be caused by head trauma.
Superior Semicircular Canal Dehiscence: Another rare condition that affects the inner ear, leading to vertigo and hearing symptoms, which could potentially be triggered by head trauma.