GMAT Strategy

Hi there,
Today I took my first mock test (ManhattanGmatPrep Test1). Scored 600(Quantitative 44(I should have done better) and Verbal(30 not sure good or bad as it is my weak area)). I had timing issues with Quantitative (finished it barely didn't get enough time for the last question) and Verbal(well in time with more than 4mins remaining).
I got 19 Questions for quantitative Wrong and 20 wrong for verbal.
The questions which I got mostly wrong were 600-700 level and 700-800(almost all the questions wrong).
I have got 2 weeks remaining and I need to know how to use those 2 remaining weeks to get better and improve my score.
And by how much can I see my actual score(on the GMAT day) swing compared to this Manhattan test. Any suggestions and help will be much appreciated.
Nimish

Thanks Eric, Still haven't done the GmatPrep Saved it for this Sunday and the Beginning of the final Week. Yeah last week I have kept for the revision of all the stuff I have already done not going to learn any new concepts just going to improve on the mistakes made and planing to go through the explanations provided in the OG material starting from the end once again.
Since my prep time has been around 3 weeks so I should be able to sum everything up in the final week.
Many thanks for your replies