Yes it is possible. MS lesions can be in the brain, or the spinal cord or both. It is 'usually' in the brain as if there's much that's usual with this disease, but can appear anywhere in the central nervous system. If you or or your neurologist believe you might have MS, often times a spinal tap will also be done despite a clear MRI to look for the presence of O-bands (oligoconal bands) in the spinal fluid. The o-bands are only found in about 80% of people with MS, so it also isn't a definitive test either.

All of that makes getting an MS diagnosis quite difficult, it really likes to hide well sometimes. However, my fingers are crossed for you that it's not what you have and if it is, that the doctors will discover it quickly, and that you find answers to whatever is going on soon.