Ear pain and dizziness suddenly developed a few hours ago, what can this be? female, age 50, hx of subarachnoid hemorrhage

Vertigo: If you have no neurological findings,i.e. localized weakness,slurred speech,drooping lip,this is most likely related to an inner ear problem. If symptoms persist,see your doctor.

Pain isn't typical : For simple vertigo. Most likely this is a result of infection in the middle ear or the inflammation of the vestibular, aka ear, nerve. This could be either viral or bacterial, and should be looked at by a doctor if the pain is severe, if there is drainage from the ear, or if you have a fever over 100.4 F even without the other elements described. Please take care! Best wishes to you.