I would personally be concerned with being on three different anticonvulsants. To me, that kind of reeks of a doctor just throwing everything possible at the wall in hope that something sticks, but I'm no expert. Have you considered getting a second opinion about your treatment? My pdoc sent me for a second opinion at one point because he wanted fresh eyes on my case and treatment. It helped confirm what he was doing (for both my pdoc and myself) as well as offering a few helpful suggestions.