persistant mild eyelid twitch

My left lower eyelid started to twitch during the first few days of this year (2007). Everything that I have read from your site and various others tell me that it is nothing to worry about. Even though it is not a severe twitching it is constant....I mean, it never stops, from what I can tell, not even in my sleep. It isn't painful, but let's face it, it isn't normal either!. I try to ignore it, but I know that it's been noticed. Does anyone on this site have more information on this, or something from their own experience to give me a better idea of what I'm dealing with before I go to the doctor. The only other time I have ever suffered from a twitching eye was before I was diagnosed with a high lever of TSH, when I started taking medication for an underactive thyroid the twitching(sever that time), stopped....go figure. Anyway, any ideas or comments would be appreciated.