I know the feeling! It’s really positive that you are getting an MRI and that should give some more clarity.
During my first 3 years of symptoms I went to the doctor’s a lot only to be told I might be hyperventilating but nothing was diagnosed. Very frustrating!
It is difficult to explain yourself and your symptoms, I have found the posts on here very helpful as some of the ways people articulate their symptoms are very effective!
You’ll have time and future appointments.