medea66,
What resources have you been using? I found that Kaplan and Princeton books were pretty much a waste of my time. Things that have been instrumental in increasing my score came from Manhattan GMAT books, the OG (orange, purple, and green), MGMAT CATs (which provide a lot of explanation to each question), and this forum.
I would not suggest doing problems under timed conditions. I believe that there are two stages to the GMAT. The first stage is the learning stage. The second stage is the practicing and solidification stage. You are still in your learning stage and I would not suggest doing problems under timed conditions (that's what you have the practice test for). Instead, move through a problem as fast as you can, but LEARN. It is better to solve a problem from the OG in six minutes, and really learn how to do it. The next time you see a problem of the same type, you will solve it in four minutes. As you see more and more manifestations of the same concept, you will learn it from every angle. THEN, you will see that your time will decrease.
Two weeks is a very short time to work with. This should really be a time when you review rather than learn. However, in your situation you have to get as much learning in as possible. I suggest that you focus on the problems that you almost always answer incorrectly. I also suggest that you focus on the problems that are most commonly tested: rates (distance and work), ratios (new men being added to a room, liquids being transferred from one jar into another, etc.), percentages (percentages of, over, increase, decrease), brush over geometry (unless you are really weak on the most basic of things), DO NOT DO any probability or combinatorics.
On the verbal section, I would focus on sentence correction more than anything else, because that is where return could be highest. You can get better at critical reasoning over a longer period of time. It requires a close and rigorous study of each question type to see what the subtle differences are between the correct answer and the second best answer. Reading comprehension is about creating enough time for you to read the passage. The way to increase your time on RC is to get better and quicker on CR and SC questions.
Let me know if you have any other questions. I'd be happy to answer them.