Hi Viv. MS may present with visual disturbances, foot drop and abnormal sensations. So this would definitely be on the list of possibilities. But these symptoms are non-specific, and may be a result of other processes. Have you seen a neurologist yet?
If there is clinical suspicion but a normal MRI, you could ask the neurologist about doing a lumbar puncture (spinal tap). While not always done early on, it can help to rule in or rule out MS. The presence of oligoclonal bands in the CSF (cerebrospinal fluid) suggests an inflammatory process like MS. The absence of these bands does not rule it out completely, but makes it far less likely.