hi kadi,

i'm glad you found our group; a great bunch of people.
first, take some deep breaths. it will be ok. let's see, some suggestions:

the MRI will probably take the longest. when the tech gets you on the table she/he should take a moment to get you comfortable. if you tend to be cold they will cover you with a blanket. take footies for your feet. shoes get uncomfortable.

they will give you plugs for your ears, the machine is loud. you'll hear some chirp y noises. or, they may offer you music. you could also bring your own.
empty your bladder.

the most important thing is to lay as still as you can. that way the best pictures can be taken. one maddening thing is that if you have an itch anywhere you can't scratch it. but, trust me, it will go away.

on the LP. people have different experiences. i had one and did well. a radiology dr did mine. it was done under floroscopy. that means the dr is able to see when the needle is in the right place. they'll give you a numbing medcine but you will probably feel some pain. it passes. drink a lot of fluids. staying hydrated helps the dr draw the spinal fluid he needs. and if you're a caffeine drinker have that too.

after the test, and when you're home stay flat in bed for 12-24hrs. it will help you avoid a headache. IF you do have a headache call the dr asap. they will be able to help with that.

sending you calming thoughts.
let us know how it all went. when is your appt?