Paper-basd tests, unfortunately, are not comparable to CATs, so you have to assume that your current scoring level is whatever you are scoring on a CAT.
As a general rule, what you are scoring 7 to 10 days before the real test is roughly what you should expect to score on the real test (within about 50 points, if you have been taking the practice tests under 100% official conditions - more variability can be expected, usually in a downward direction, if you have been doing things like skipping the essays, taking longer breaks than allowed, not doing the test in one sitting, etc.).
What that means, essentially, is that you should expect to score in the 620 range, not the 700 range, if you do take the test in a week. If that's not what you want, then you will need to postpone your test date. I know that's probably now what you want to hear, but it's better to know now so that you can make the right decision for yourself.
Mental stamina is definitely a major issue on the test, and something we need to practice. Part of that is again going to be practicing under official conditions and studying in 1-hour blocks where you DO NOT STOP or give yourself a break during that entire hour (then a 10-minute break, then another hour with no stops). This article can also help, if you feel like this is what is happening to you:
http://www.manhattangmat.com/blog/index ... you-crazy/Do you have any timing problems? If you're not sure, use the below article to analyze your most recent MGMAT CAT:
http://www.manhattangmat.com/blog/index ... ice-tests/(Note: you can finish a section on time and yet still have serious timing problems. Check the data according to the directions given in the article.)
If you do have timing problems, they typically take at least 3 to 6 weeks to fix, depending upon how severe they are. This article can help:
http://www.manhattangmat.com/blog/index ... anagement/Let us know what you decide to do. If you decide to postpone and want to discuss how to use your study time, then do the analysis described above on your most recent MGMAT CAT and then come back here and share that analysis with us. (Note: don't just share the data; tell us what you think it means! That's an important self-assessment skill to develop.) We'll help you figure out where to go from there.