Please help me !!!

hi guys,

i have given my GMAT 2 days earlier and scored a 470!!!... i dont know what happened when i consistently got in the range of 550-590 in my prep tests. my target was atleast 600(i have a specified school in mind). i was almost sure that i will remain in 550 range and planned to retake the test, but when i saw a 470, i dont know if my preps will even help!, i am so depressed to see my score that i lost the trust in my ability to prep for the exam, i have done og twice and went through some other materials. i knew i wasnt good enough, but i didnt know i was this bad. i want to retake the exam and score atleast 150 points and above. can anyone help me plan my study???. i will only register for gmat after i feel a consistent increase in score in prep tests, so i am giving my self atleast 3 months time, how does that sound?? will i be able to increase 150 points in 2 months time? i am willing to keep my entire social life for this, i am already a graduate and have plenty of time with me before the exam. please guide me anyone, i am in desperate need for help.

thanks

P.S I am planning to go through manhattan 8 strategy guides and giving a week for each of them and going through og again. is this enough?? or do i need to go through more?? please suggest