Welcome to this forum Fordy,
I would certainly go to a neuro but you need a neuro that is an Neuropathy expert, not just a normal neuro, it can make a big differance to the outcome.

The EMG & Nerve conduction test has only tested your large nerves, which doesn't mean you don't have PN, your symptoms are similar to small fibre damage, i wouldn't go for a skin biopsy to confirm small nerve damage, they are time consuming which of course means expensive and normally only done as a last resort to confirm small fibre damage, they good for comparison of damage over time though, they normally will do thermal testing which are only a couple of electrodes placed on your feet and shows how you react to the sensation of heat and cold and another to test vibration reaction, its your small nerve job to interpret & send correct signals when they feel pain, heat, cold & vibration.
In my early days of PN I had an idiot neuro that tested me with a nerve conduction test and wrote back to my GP that i showed no signs of Peripheral Nueropathy, my feet were on fire, tingling, electric zaps, i showed all signs of small nerve damage, see, this is why you need a neuro that is a PN expert, nothing less will do.
Learning as much as you can about PN is a good idea, check out on the front page up top were it says " important links and stickies " there you find a lot of good PN info and Liza Janes spread sheets show all the possible tests for this disease, which is great for keeping a record of all tests performed and also good to see all the tests that are available.
Having Pn in the feet can be possible pressure in the lower back, an MIR should sort that out though.
If your not sure about anything just ask,
good luck
Brian