I used to take gabapentin in fairly large amounts. I never really experienced any side effects, but then I have always been an expensive date. I also never knew if it was doing anything, as my symptoms progressed while I was on it. Of course, they may have progressed more it I weren't on it.
I switched to Lyrica just to try it. There doesn't seem to be any difference.
I find that my feet feel much better in warm weather, which it is now. There are so many variables as to how I feel, including emotional ones. It makes it very hard to decide what is working or not, as you probably know by now.
I don't get the sense that that either of them work right away. In my case, if they work at all, it seems to be a cumulative effect over many days. You may have a different result.
Keep experimenting.