hi amy and welcome to NT,
with the sx's you describe i would seek a 2nd opinion. get copies of the mri on a disc and ask for a copy of your dr's dictation. start a medical file on yourself. you can always call your local MS society and get references to other neuros.

it seems to me that a brain mri would have been helpful. IF you have MS the dr will look for certain lesions in parts of the brain. i too am very heat intolerant. i get the same sx's and am almost paralyzed if i let myself get too hot. you will learn how to manage this. listen more to your body and get cool as needed. walmart has $5.00 cooling collars that help keep you cool.

i think your idea of seeing an opthamologist is a good one. anytime you have changes in your vision it's a good idea. let us know how you're doing.