I was on neurontin for two years, and then switched to Lyrica. I had side-effects very similar to what you describe, and they failed to go away even after three months, so I quit taking it. Then again, I have heard many other people say that they had great results from this med. It much depend a lot on your own personal chemistry. I was taking 300mg daily, so I don't really see what you're taking as a really high dose.

Like JackMana, I finally switched to amitriptylene, except that I take 100-150 mg of that at night before bed. It helps me sleep and keep on weight, but has no pain-relieving effect that I can tell.