I'm really glad that you posted your concerns here. So far you have received excellent advise from Serafena and LFW.
The only thing that I can reiterate (by being a bi-polar myself) is to get in touch with your doctor and let him know what is going on. The signs point to you needing a medication adjustment. Don't worry, I don't think he will take you off the Lamictal.
Keep us post of your progress.