Try your best not to freak out...MS is a diagnosis of excluding other diseases and disorders, and is difficult to diagnose...
MRI should be an enclosed machine with T3 intensity and contrast given...it will give the doc the most specific information on what is going on in the brain.
Lumbar puncture will indicate any active stuff going on in the cerebral spinal fluid...if you do need one, make sure the morning of you drink plenty of liquids, and afterwards, lie flat all day and drink caffeinated drinks like Monster or Rock Star...it is very important, since you may develop a headache otherwise. I did the above and had no headache or aftereffects.

Keep a symptom journal with dates of onset of symptoms...not to be a hypochondriac, but to give info to the doc at your appointment.
Also keep a list of questions that you might want to bring up at your next appointment....I know personally that if I try to keep a mental list, I forget what I was going to ask as soon as the doc enters the room
I would also suggest bringing someone with you to your appointments...it is wise to have another set of ears in case you miss something...

Try your best to live your life to the fullest-many MSers here try their best to make the most of every day to the best of their ability. MS is not a death sentence...it's a "wake up and smell the flowers" sentence...

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