I just Beat The GMAT!

Hello guys,

I have been studying fot the GMAT for over 3 months, my first CAT without any knowledge or instruction about the GMAT was 210 (I couldn't finish), my second CAT was 370 (two weeks after studying at Kaplan), my 3rd CAT was 560 (Kaplan's CAT, a week ago) and my last CAT 530 (Official CAT, today). I have been Studying very hard, at least 5 hours a day and over 8 on the weekends.

I am taking the Kaplan on site course (for the second time, one after the other).
I am using the Word Translation guide from MGMAT.
And I am using the Official guide.

My weak area is algebra, I study and understan but every time I see a new problem I can't work on it.
My RC is weak too, I get lost so easy.

Any advice? I have 3 weeks but I don't know if I should pospone the test. I felt so close when I got the 570 on my CAT but then today's 530 brought my confidence down.

Thank you for your help.

I am venezuelan, 28 years old, planing to apply to St. Gallen International Management program and I need at least 600 to send my application.