I need some honest opinions about taking the feb LSAT (yes, it is this Saturday - the pressure is clouding my judgment!

So: Would it be better to see how I do this time around and retake in June, or wait till June and get just one killer score. Since I am aiming for HYS, would I hurt my chances by getting a lower than score than I was capable of the first time around?
Many thanks for your thoughts and comments!
Also, for anyone who has any knowledge or experience: what kind of difference would 'killer' extra curriculars do for my application to such schools? I was president of the student union for a year and have represented the Swiss youth at the U.N. among other things. Would that make up for one or two points on the LSAT or do most others have similar kinds of experience and it would make little or no difference? Guess I should do my best anyway but since many people with killer LSAT scores and stellar GPAs still get rejected, I am curious nonetheless. Would have done a sperate post on this but figure there was a small chance both questions could affect each other.
Cheers!