I don't think your to clear with what a Nerve conduction test is, it doesn't measure how much damage you have to your small nerves, the small nerves job is to let your brain know of how much heat, cold, and feeling vibration, they are feeling, thats all.
To test how small nerve damage there is they can hook you up with a couple of electrodes and do test to see your reaction to heat, cold & vibration.
If thats not enough then they can do a nerve biopsy or skin punch, then under special testing they can see how much damage, but this is usually a last measure, because it costs $$$$.
An EMG will measure the larger nerve damage,which some say it hurts but didn't worry me in the least, same as a Nerve Conduction test as i wrote back to your prior post which i don't think you seen because it wasn't answered at all, perhaps it depends on the amount of nerve damage to the individual or may even be the skill of the operator, i really don't know.

Seems like your pain is helped at night but you are in trouble during the day when you need good pain relief, perhaps they can alter the meds a bit and cover your pain during the day, i found 300 mg Tramadol Slow release x 2 - helped me a lot during the day and the night and best part it didn't make me feel dopey, or the druged up feeling you can get form certain drugs like Oxycontin, Neurotin etc, but of course you have to talk to your doctor about appropriate meds to help you through the day.
It also sounds like you have a good doc thats offering you good advise to adjust your meds to suit your needs.
I really do hope that you can find a lot more relief than your getting right now.
good luck
Brian