For this question, I'm going to point you first and foremost to our article on evaluating our practice tests: http://www.manhattangmat.com/blog/index ... ice-tests/
We have analytics on our exams, and this article really helps you to use those to your best advantage.
As for feeling panicky on the real exam, the exam is actually structured to make you feel like that, because it will constantly be looking to give you questions that are ABOVE your ability level. So make sure to stay calm, take the two minutes if you need them, but if you feel that a question is beyond your ability level, make an educated guess and move on. The GMAT is really great and getting you to spend 5 or 6 minutes on a tough problem, but in the end this will hurt you more than it helps! In terms of feeling panicky, I would point you to these two articles on managing stress, which may help: http://www.manhattangmat.com/articles/m ... niques.cfm
and http://www.manhattangmat.com/articles/m ... s-tips.cfm
It would also be helpful to know a little bit more about HOW you are studying. You mentioned that you are doing 30 hours a week and taking one exam a week (which seems to me like it might lead to burnout, so be careful and make sure to take time off when you need it!) but what exactly have you been doing to study? Have you been working through the content/background that we have in our 8 strategy guides? Have you been working solely from the OG solving problems? Or is it a combination? You mentioned you were timing yourself with OG problems, which is great, but there are a lot of other areas where you may be able to make the actual time you spend studying more effective. For this, I would point you here: http://www.manhattangmat.com/blog/index ... tudy-list/
I hope this helps!
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