You have to wait at least 31 days to take the test again - I'd say 4-6 weeks given the difference between your score and where you want to be.

You need to be very systematic in your prep. Log all of your errors - not just the fact that you made an error, but what the error was and (if possible) why you made it. Examine the log for patterns and figure out habits you can build to break the habits. (One good habit is to write EVERYTHING down so you minimize careless math errors. I literally will write down 2+2 when I take the test - it doesn't take any more time to write it than to think it, and if I make some really silly mistake, my eye will catch it most of the time.)

Part of your study needs to involve being able to recognize what to do with a problem within the first 15-20 seconds - recognize, not figure out. The more problem types you can recognize, the better you will do on the test. You will have some you don't recognize, of course, and then you will have to figure those out from scratch. Break any problem down to its bare bones, its basic structure, and figure out what the language or set-up is that lets you know what the problem is about and how to do it. Then you can start to recognize other problems that are different but have similar "bones" and that gives you a jump start on solving that problem.

You also need to work on your educated guessing strategy so that you feel more comfortable letting go on problems you really can't do within 2 minutes. As you found, if you get yourself into timing difficulties, it is extremely difficult to recover.

Finally, you know you've mastered a problem when you can teach it to someone else. If you don't have a willing victim, try your cat or the mirror - but do actually try to explain it out loud (and don't forget to explain what the traps are or why the wrong answers are wrong), because your strengths and weaknesses will become very apparent when you do this.