Hi - I had an amnio back in the summer, after getting high risk NT results (well, classified as high, but at the 'better' end of the scale).
Originally went for CVS appt, but consultant advised holding out for amnio due to location of placenta (a CVS would have been higher risk). Was still a bit uncertain about whether to go ahead with the test, but turned up on the day, got scanned, talked to the consultant loads about risks etc and only then signed the consent form.
Procedure was relatively quick and painless - no local anaesthetic given as apparently this hurts more than the procedure itself. Minor pain for a day or two but nothing to write home about. Unfortunately, the day after the procedure, I had to make a very necessary 500 mile road trip to see a very ill relative. Was very worried about the effect it would have on the baby, but the doc said it would be fine, and it was (resting is advised for a few days, but apparently it doesn't really have any effect on the outcome/risks).
I was able to get the baby's heartbeat checked the day after the tests too, and that was very reassuring.
Regarding results, they very kindly speeded up the results for me, and I got the provisional all-clear on the phone just over 24 hours later. That was an immense relief, but then did get a bit anxious all over again when the two week wait for the absolute results was nearly up. They were all clear too, which was great!
Sorry for long waffle - wishing you all the best for your tests tomorrow. I fully understand your need to know - talk as much as you want to the medical people before the test to get the information you need (if that's what you need to do) and then be kind to yourself afterwards. x