Hi, Colin. I'd get a copper test. Since you take zinc regularly this may reduce your copper levels. (they are a duo and work together, and when one gets high, the other gets low).

I'd check your magnesium to see if it is NOT oxide form. This is not absorbed and stays in the bowel to be excreted. You will need a chelated form like glycinate/citrate/carbonate, etc, or SlowMag, instead for better absorption.

People who use Klonopin (or any benzo like it ) every day, can develop mini-withdrawals, in between doses. Benzos are highly problematic long term, and difficult to withdraw from. You would need to discuss with your doctor using another sleep medication like Ambien. Your taper will need to be slow. You can Google "benzodiazepine withdrawal taper" to see other suggestions on the net.

It takes a long time to get off Benzos, so it will not be pleasant, but your twitching may be due to the decreasing Benzo levels in your blood.

Loss of sensory nerve fibers may be inherited too. Do you have any blood relatives with this problem?
Toxins, and some drugs also damage nerves. So look back to your antibiotic use in the past, exposure to solvents, or pesticides, heavy metals, vaccines, etc to see if any culprits can be found there.

This is our Peripheral Neuropathy forum with a subforum with lots of information to learn about to help you further:
http://neurotalk.psychcentral.com/forum20.html