Hi,
All d best 4 ur xam! Do not think so much now as there is not much time left before the actual xam. Have u given any 1 gmatprep test? They are very accurate. Regarding your CR, I would suggest the following:
1] Break down the argument into background, premises, counter premises, intermediate conclusion, conclusion, etc (DO NOT skip this step)
2] Pre-think (at least 1 answer, which may not match the actual answer)
3] Eliminate the answers which appear wrong until you are left with only 1 answer
This is also mentioned in the Powerscore Bible, the problem is that even after learning these steps, we tend to ignore 1 step or the other. Try to follow each step and practice atleast 10-20 questions from the Gmatprep tests for the next few days.
AL d best!