I had decompression surgery for my Chiari a year and a half ago and have just started having the same symptoms so could very well be related to Chiari.
I have very similar symptoms to yourself, spent over 18 months of blood works all came back normal. I was also referred to rheumatologist last year, as had pains in legs and quite sensitive to coldness too and was diagnosed with rynueads level one. However pains, twitching muscles, and numbness in fingers also. Generally very fatigued even after a good nights sleep, feeling anxious as wondering if something awful was wrong with me as feel dreadfully tired along with these pains and tingling. They know diagnosed me with chronic fatigue syndrome, I would ask if you could be be referred to rheumatologist and be persistent if no improvement. ME/CFS/FIBROMYALGIA is still not great understood or picked up on from most GP’S unfortunately, I was constantly told beforehand it was probably stress and stress can effect the mind/body. Only thing as I was stressed about at that time of my life was feeling like this, thou not a great deal can be done at least I’m not freaked out thinking the worse anymore. Hope this helps you out.
I've had very similar symptoms, and all tests also came back "clean". Currently I'm taking 75mg amitriptyline a day; this stopped the muscle twitches and concentrated the general tingling into a couple of digits, and I have a persistent "buzzing" in my face. I'd also recommend some Magnesium, Potassium and Sodium supplements which may help with the muscle twitching.
Please call your neurologist's office EVERY DAY to see if they have a cancellation and can see you that day.
MS, ALS, Parkinson's are all worse case scenarios and there are a host of other factors that can cause these symptoms.
Could this be Parkinson's? Do see the neurologist and good luck.