Isolated vertigo is unusual in MS, as in this part of the brain there are many closely packed areas that are also affected if there is an MS lesion in this area. So without other evidence of MS, isolated vertigo is unlikely to be MS. What is more common as a cause of vertigo, which is very sensitive to movement of the head, feeling awful, and lasts a few days, is 'benign positional vertigo' caused by dislodegement of some of the inner ear particles that detect and control balance and motion. There is effective treatment in the form of specific positional maneuvres. If it happens again, see a oto-neurologist or ENT.
MRI lesions that are ovoid or transverslt oriented to the brain ventricles are suggestive of MS. That is why they specifically state that they were not present.
Advil can be taken up to 15-20 times a month. More frequent use cna result in medication-rebound headache. If headaches are occurring more frequently than this, you probably need another type of medication to reduce the frequency of the headaches, see you neurologist for more details