Hey Ashley,
Let me add my 2c to Nicholas' excellent post above.
Accuracy is indeed key, and so it is critical to evaluate exactly
why you're getting some of these questions wrong. This question is harder than it sounds. There isn't always a consistent correlation between question types and accuracy: as you notice yourself, you are "all over the map" when it comes to what types of questions you're getting wrong. Only the luckiest students can point to, say, Flaw questions and say, "Alright, I'm getting all of these wrong, and the rest of my section is virtually flawless, so I have my work cut out for me." Unfortunately, many (most?) mistakes are not - or at least not
only - the result of conceptual misunderstanding of the question type. Rather, they stem from a variety of other factors, such as rushing or misreading the facts and/or the conclusion of the argument, inconsistent prephrasing or no prephrasing at all, pacing issues - forcing you to guess on a large number of questions, etc.
If I were you, I'd take a long hard look at my most recent practice tests and figure out not only what types of questions I'm missing, but also what types of arguments they contain. Maybe you have trouble manipulating causal arguments, or lack the requisite technique to diagram conditional relationships. Maybe you misunderstand arguments employing numerical evidence. If you're running out of time on some of these sections, review not only the questions you got wrong, but also the ones that cost you valuable minutes - even if you got them right. Clearly, your approach was not optimally efficient if a particular Parallel question took 3 minutes to solve.
Ultimately, breaking through a plateau is a difficult task - something you may or may not be able to achieve in a week. If you don't, you need to reconsider whether it's wise to take the test in September, or wait until December. Of course, this is a personal decision that will depend, at least in part, on how far off target you are, how comfortable you are with a (slightly) lower score, and whether or not you can dedicate the time and energy to continue prepping until December.
Check out a few of the most recent posts we've written relevant to some of the issues you raise:
http://blog.powerscore.com/lsat/get-a-g ... -lsat-prep
http://blog.powerscore.com/lsat/did-you ... t-practice
If you have specific questions about the PT's you've taken and reviewed, don't hesitate to post them on the forum.
Good luck!