Nerve Conduction Study/Spinal Tap - What's it like?

I am very new to all this.  I had an appointment with my neurologist yesterday and he has ordered a nerve conduction study on my arms and legs as well as a spinal tap.  Both of these tests will take place in the next few weeks.  Can someone give me some insight on what to expect?  I also had blood work to look for rheumatoid arthritis, lupus, B12 deficiency, and lyme disease (among other things).  At this point, I am primarily concerned about the nerve conduction study - I know the spinal tap is going to be awful!  Is it painful?  How long does it take? is there anything in particular I should do to prepare for it?  Any advice/insight would be appreciated!

[AMO]

hi jonesnc,

how  are you toda y?
how were   the blood work results?
are you having neuro ssystems wiwth dysautonomic ones?
amd when do you have schedules for these test?

i havvve had two of each these. my advice, don't work yourself up over them....
i had booth l.p. done     inoffice from my neuro, no fundoscope(sp for a x-ray like shows s where the needle goes?)
The key is having expert haan  ds! I can not rememebr how long they took....hour?

I  did not get up 30 mins or so after, then laaid down  on my car ride home   (3 hours drive), and after at home. I did not     lift thingss andd tried being quiet for a   couplel days. Drink fluids...lots, some people drink caffene. I lounged around aaaand just up for the bathroom.It is a good time to havee someone wait on you:)) It did not hurt at all, just a sting  for the lidocaine .
My back at the site was ever so slightly  sore and 2nd time litle bruise. Third day i was doing what I wnated.... just take it EASY and not    overdo.

I  had two  EMG-NCS also....were cake too. Don't wear any lotions or such on your skin.
I can not rememebr which part  i felt some zaps , but faintly. Hardest part was trying to tense mmy muscles. How long they are how many muscle goups they test.

I knowo they seem scarey, but rememeber just keep calm and htey are over quick. no big deal:)
take good care, amo