Thanks for using the forum. I am happy to address your questions, and my answer will be based on the information you provided here. Please make sure you recognize that this forum is for educational purposes only, and it does not substitute for a formal office visit with a doctor.
Without the ability to examine and obtain a history, I can not tell you what the exact cause of the symptoms is. However I will try to provide you with some useful information.
I am not sure what you mean by the term dizziness. When some people use the term dizziness, they often mean vertigo, or room-spinning. Others mean a light-headed, whoozy feeling.
If by dizziness you mean vertigo (room-spinning), the causes could be either the inner ear or the brain. Inner ear causes of vertigo most commonly include benign positional vertigo (BPPV), which is due to small particle in the inner ear that moves out of place, and can be repositioned with simple head maneuvers. The symptoms often include vertigo that occurs with turning of the head, often while turning over in bed. Another cause, if your symptoms are associated with tinnitus (ear ringing) and hearing loss is called Meniere’s disease and can be treated with medications and sometimes surgery. And so on, several other causes from inner ear problems exist.
Vertigo can also be due to problems in the brain. The most common is a benign tumor called a schwanoma (also called acoustic neuroma). This is diagnosed by MRI of the brain. Multiple sclerosis can cause vertigo, but often, other symptoms are present as well. A normal MRI of the brain excludes these. Thyroid problems can also lead to vertigo.
If by dizziness you mean light-headedness, causes could include low blood pressure such as due to dehydration or autonomic dysfunction, cardiac problems, and several other non-neurologic causes. Anemia can cause light-headedness as well.
Based on your description, your symptoms do seem to be peripheral (inner ear). It is difficult to say if you have had a seizure in the past or not. A normal MRI is reassuring.
If you have not done so, I would recommend that you obtain vestibular rehab. This is a specialized physical therapy focused on coping and treating dizziness. You should also continue following up with your neurologist.
Thank you for this opportunity to answer your questions, I hope you find the information I have provided useful, good luck.