Perhaps results of the other tests will narrow the focus of attention for you and the doctor. Presumably you've told him about the Bell's Palsy? I have heard of folks who have experienced that, and found that it was a sort of "precursor" to MS developing later -- not that Bell's Palsy really is a precursor...but what they had wasn't really Bell's Palsy at all, but problems with facial nerves that sometimes happen with MS.
Lots of us overlooked stuff early in our course of developing MS, thinking "everyone has that!", or being told "everyone feels that way!" by people around us. So that certainly is a possibility.
Also, lesions can appear long before any external signs are evident. In fact, people have died of other causes, and had an autopsy done -- and lesions have been found that were suggestive of MS, yet the person had no external signs! So that's a possibility.
And lesions can appear for other reasons than MS -- migraines, some infections of the central nervous system, vascular problems -- all can lead to lesions. So the doctor is being prudent to run all sorts of other tests to rule out -- or rule in -- all other possible causes of problems, before giving you some firm diagnosis.
I hope you get some direction from the test results.