I Have A Very Painful Stinging/burning Sensation In My Inner

I have a very painful stinging/burning sensation in my inner lower lip and on the base of my lower gums. NO visible cankers or anything, but it feels like a thousand microscopic canker sores (its the best way to describe it). I can't even eat good or talk good b/c it hurts so much. I keep getting "bouts" of this since Feb. This "bout" has been 4 days now.