Feeling very discouraged, please help!!

Well, I took the first GMATPrep test for the first time last weekend and got a 520 I still wasn't too discouraged because my timing was completely off. For the math section, I had 17 questions left with 12 minutes remaining and I ended up guessing "C" on 10 straight questions (9 of which I got wrong). I believe my scale score was (Q35 V24) something like that, can't remember the exact score.

I took the same test again because I knew I missed alot of questions and would probably see new problems. This time I got a 590 (Q39 V31). This is very discouraging. I am aiming for 700 and I thought I was pretty prepared for the Quant section. But my score obviously doesn't show that. Also, I am very discouraged with the English score.

I started studing at the beginning of March and spent about 1-2 hours a night studying math and about 3 hours each on Sat and Sun working mainly with OG11 and doing some problems on this forum. I clearly need a better study plan.

But my main dilemma right now is that I have the test scheduled for May 21st and have 2 weeks left. Obviously 700 at this point is out of the question. Would you recommend that I reschedule the test for the additional $50 and move it to July? Some people have told me to go in and take the test anyway just to get the experience, but at this point seems like a waste of money. Please help!!