My first game was like a huge shot of addiction-creating adreniline. I have yet to lose the craving.
From what I recall (and memory joggers from other newbies), your first game will seem like EVERYTHING is happening and you are only seeing a little bit. Most of this is because you have not developed "filters" to focus on your PRIMARY area and learned to anticipate the action which allows you to get in the best position.
Do not be a ball-watcher. If you need further description I suggest you get find a local mentor to help you with the many questions you will encounter as you get court time.
Best wishes and HAVE FUN!