OK - this detail is very helpful.
What I'm reading here is that you 1) want to be more competitive for admission to top schools, and 2) for multiple reasons, your GMAT exam experience was less than optimal for you. That makes complete sense, and I completely understand your frustration.
Given this information, there's definitely a possibility you can improve your score if you were to retake the GMAT under more optimal conditions.
My recommendation would be to pursue application for Fall 2014, and use this application cycle to retake the GMAT, and strengthen your quant skills. Developing the quant skills (by taking quant courses - perhaps the UCLA Online Extension courses?) is not for the admissions process, per se, but is more for when you are a student in the MBA program you will ultimately pursue.
I've worked in MBA programs for 16 years. I frequently observed students struggle greatly with Accounting, Stats, and Finance - due to the heavy quant load, and frankly, the crazy pace of an MBA program. If you take some courses before you go into the program, you'll be more comfortable with those courses in the MBA program, and you'll reduce your stress level as an MBA student.
I hope this is helpful to you. If I can help further, please let me know!
15 Years as Director of MBA Admissions - Now Working For the Applicants as the MBA Admissions Coach
Wendy Flynn is the MBA Admissions Coach, providing comprehensive MBA admissions consulting services. As the former Director of MBA Admissions for 15 years at a top-30 MBA pgoram, Wendy holds deep expertise in admissions issues for Full-Time, Executive and Professional (Part-Time) MBA Programs. Through her blog, MBA Expert Insights, she brings the view of the Director of MBA admissions to MBA applicants and others.
MBA Expert Insights Blog: http://www.mbaadmissionscoach.com/blog/
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