Hornet and others have posted so accurately the situation. In your case, most definitely finish out the semester.
I just wish many of those applying would read this and similar posts. I don't care "How Long you've always dreamed of this", the academy and the military will not be what you dreamed about for the last 5 or 10 years. And when you graduate the academy and move on to the "Real" air force, it too won't be what you thought it was going to be.
Those who do best, or have it easier, seem to be those that have no idea of what they're getting into; and they admit it to themselves from the beginning. There's no expectations. This way there's no disappointment, second guessing, etc. They simply take it for what it is and decide whether it's something they can do and live with or not. The other group that tends to do well are the Brats. Not because they are use to the military attitude and upbringing, but because they know that the military is always in a state of flux and that the politics involved will dictate a certain attitude. Basically, they already know the good side, but they are aware of what really sucks about it too.
Don't get me wrong. I love the air force. I wouldn't have traded my 21 years under any circumstance. There are so many positives about being a part of it, and being an academy grad and officer. Simply saying to all those that "Dreamed of this their whole life", and those who think they have a foot up because they were in JrROTC, CAP, Boy Scouts, etc... throw ALL of that out of your head before applying, accepting, and going to the academy. JrROTC is NOT similar to the academy and the air force. Neither is CAP, Scouts, or anything else. It also doesn't matter how long you've dreamed and wanted this. The air force, academy, and military is not the same as it was when you were dreaming of this years ago.
If you apply, receive, and accept an appointment to the academy, simply accept the fact that it is not and will not be the same military that you dreamed of or think you have knowledge of. If you're a brat, I'm sure your parents have told you a number of times how the military is always changing. They mention the politics. It all comes down to being similar to being the new kid at school or to the neighborhood. You'll have a lot of people telling you who's cool, who's not, who's bad, etc... You have to make up your own mind and develop your own impressions of the academy and military. If you don't go in with any preconceived perceptions, you'll do much better. Same with any job, town, school, or person. Walk in with an open mind and make your own opinions. If it's right for you, continue on. If it's not, then move on. No harm, no foul. I've said it many times. It never bothers me when a cadet goes to the academy, gives it a serious try, and decides it's not for them. That's cool. Just warning those who aren't in yet..... go in with an open mind and decide for yourself. Don't go in thinking you know what the academy and military is all about, simply because it's something you've always wanted or because you were in JrROTC, CAP, or scouts; or you were a Brat. You won't know until you get there. Make your own decision.