Well, I tried a lot of things, various vitamins and diet changes, and while I started feeling better, the pain and twitching never fully went away. So I went one more time to the doctor and asked for a B12 test. I read a few anecdotes online about B12 causing neurologic issues and how you can have a normal blood test and still be deficient. The last few doctors ran blood tests, not B12 tests, and those always came back normal so they insisted I don't need a B12 test because those other tests would have shown something. Well, B12 test came back at 235, which my doctor said was still low normal so didn't think anything of it. I went to the pharmacy, bought a bottle of B12 1,000mcg and started taking it once every morning. It's been almost two weeks now and my symptoms are about 80% better. I barely notice the twitching, it happens only a few times during the day now instead of all the time, and the pain is gone from my hands and legs.

Not sure what to do now, whether this is actually it or not, but it has made a difference for sure. Seems B12 ranges differ a lot from lab to lab, but I'm assuming I'm on the low end and near enough to be experiencing some odd sensations like what I've been dealing with.