Hi corbe0819,
Many Test Takers spend 3 months (or more) of consistent study time before they hit their 'peak' scores. Since you studied for just 4.5 weeks, this 590 is a solid performance (the average score on the Official GMAT hovers around 540-550 most years). I'll be happy to analyze your ESR - you can feel free to PM it to me. I'd also like to a bit more about how you've been studying and your goals:
Studies:
1) What study materials have you used so far? What materials are you planning to use going forward?
2) How have you scored on each of your CATs (including the Quant and Verbal Scaled Scores for each)?
Goals:
3) What is your exact retest date?
4) When are you planning to apply to Business School?
5) What Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich