There are several causes to feeling dizzy. It could be inner ear related, infections, change in head positions, vertigo, Meniere's disease, which affects the volume of fluid in the inner ear, neurologic disorders, diet, food allergies. There is no way to pin point the exact cause without further evaluation. Sounds like you have had a lot of good tests already. Have you seen a neurologist yet? This may actually be migraine related as well. I would follow up with a neurologist as well though for further evaluation. Also request an MRI too.
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