Hi Hoozan,
From what you describe, your general math knowledge and skills are probably fine, but the Quant section of the GMAT is NOT a 'math test' - it's a 'critical thinking test' that requires lots of little math steps as you work through it. Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) When did you take your 1st Official GMAT and how did you score (including the Quant and Verbal Scaled Scores)?
2) How long have you studied for the GMAT in total? Over the last 2 months, how many hours do you typically study each week?
3) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
4) What is your overall goal score?
5) When is your next Official Test Date?
6) When are you planning to apply to Business School and what Schools are you planning to apply to?
GMAT assassins aren't born, they're made,
Rich