Please critique my progress so far

I've been studying for about 3 months now.

Here's the time line so far.

- I first scored 540 without studying
- Bought all the necessary books: OG11, Quant Review, Verbal Review, MGMAT SC Guide, Kaplan 800
- Was scoring between 560-620's on the GMATPrep's, took them about twice each
- Took the MGMAT practice test and scored about a 620 on the first try, then a 670 on the second.
- Studied for 2 months or so, with HARDCORE cramming the week prior. Got a 520 I could blame the low score to sleep deprivation.
- Took a break from studying to write essays (2-3 weeks)
- Continued studying for another 3 weeks or so, took the GMATPrep again, this time scoring 670-690 each time (Total times taking GMATPrep is about 4 each) I got 47-49's on Quant and about 30 or so on Verbal.
- Decided that the scores were inaccurate, since a lot of the questions were repeated and I already knew the answer
- Bought PowerScore Critical Reasoning Bible - read the first 30-40 pages, which helped me to learn some good CR concepts. Not sure if I should spend time reading the rest of the book or practicing CR problems.
- Took the Kaplan Practice test (which I know is supposed to be harder, or at least you get a lower score) and go ta 630. (37Q, 41V => WEIRD, I am better at Quant, and always have been. Usually score about 43-49.) Not sure that it affected me, but I took this exam at 7AM without any sleep, insomnia's got me right now...

I'm aiming for a 670-700 right now... 700 would be GREAT! What do you think is the difference between the Kaplan score and the official GMAT score? BTW, I'm retaking the GMAT on April 28th.

Basically, right now I am pretty strong in quant, at least in the common problems. I'm going to keep practicing the concepts that I have not reviewed yet. Also, I need to keep practicing SC so I can get that down perfectly to improve my verbal.

Please help me focus and stay determined! I want to know what I should do in the week I have left to maximize the efficiency of my time. I'm so ready to pull the plug in a week.

Oh, also, one major mistake I consistently make are CARELESS ERRORS!! Is there any way to focus better to help read exactly what is being asked? For example, If it says "How many even prime integers?" I might miss the word "even" and count 1, 2, 3, 5, etc.. and get it wrong. Or just simple arithmetic errors like, where I would have gotten the question right, but I was just so silly.