Hi sheldoncooper,
Since your original posts were back in mid-February, and now you're posting 3.5 months later, there are certainly some questions about the studying you've done during that time. You've admitted to NOT properly learning the 'basics' and not pushing yourself very hard, so both of those issues almost certainly played a role in your earning a 590 on Test Day.
1) What was your study routine? Did it change once your new job started? How many hours did you study during a typical week?
2) What practice materials did you use?
3) How did you score on each of your practice CATs (including the Quant and Verbal Scaled Scores)?
4) What were your Quant and Verbal Scaled Scores on the Official GMAT?
While feeling disappointed with this score result is understandable, you have to remember that the GMAT is a consistent, predictable Exam - so you CAN train to score at a higher level. One of the 'keys' though is that you have to commit to the process; from what you describe, it doesn't sound like you fully did.
GMAT assassins aren't born, they're made,
Rich