To the original poster: Dude, I was in the same boat as you about a year ago. I was jumpy, tense and I worried about killing the ball just to compete with the people I was playing with. I took about a year away from the course (To compete more heavily in national level tournament paintball) and when I got tired of wasting all of my time and money on paintball I decided to hang it up and take up golf again. Well, I went to the driving range about a month ago and to some surprise I lost most of my swing flaws... I guess I have calmed down in the past year. Long story short, Just calm down and swing. Dont think about hitting the ball. Swing just as you would with a practice swing and keep your movements fluid and dont stretch too much trying to have a perfect "Tiger-like" swing. You will probably find that you were just trying too hard and thinking about too many things while addressing the ball... hope this helps you, I hate when people give up on things just because they dont go pro within the first couple of weeks.
My best friend went and spent 700 bucks on a brand new competition bow and we went up to the local indoor shooting range yesterday and after shooting ten or twelve shots he puts the bow down and says "Oh well, I guess that was 700 bucks wasted, I cant even hit the bullseye" He honestly wanted to quit shooting and decided that we should leave.
Just keep at it, sooner or later you will get the hang of it.