Brief Answer:
BPPV vs central origyn.

Detailed Answer:
Hello. I have gone through your question and understand your concern.
In case of a sudden onset ther are two possible causes of origin.
1. Peripheral origin of the vestibular nerve. The most common cause is Benign Paroxysmal Positional Vertigo which is a benign condition, with sudden onset generally involving spinning object feeling and unsteadyness to one side. It is caused by otholit disturbance in the inner ear. The diagnosis is done by Eaply manouver which consists in head movement but to be done by a specialist. The treatment consist on Betahystine in long terms and some reports stating the benefits of mannitol in the first three days. The last option is considered obsolete by most neurologist, but I have seen good results with it.
There us also a second cause of inflammation of vestibular nerve.
Both of these conditions are self limitted and benign lasting from some days for the former to several weeks for the last.

2. Central origin. This is caused by some disturbance on the blood flow in the brainstem. If you have other symptoms, such as numbness on the left face or tongue, facial weakness, weakness or numbness on arms or legs, this might be the case which is a more serious condition, reason for which a CT or MRI is needed.

Basically you need a physical neurological exam.

Hope this answers your question, please feel free to ask other questions.

Wish you good health

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