Hi elti,
First off, 700 is a really solid score! I understand that your score has dropped a bit from your practice exams, but it’s still a great score.
Based on your debrief, it’s clear that stress, nerves, and lack of sleep negatively affected your performance on test day. Regarding your study routine, I don’t think you need to make any drastic changes. Clearly, what you’ve been doing has allowed you to get to a high level in verbal and quant. The biggest key for your GMAT success is to keep your anxiety at bay. One great way to do so is to develop a positive attitude and be confident. Look, you’ve scored 720+ on multiple practice GMATs, right? So, look in the mirror and tell yourself that you are pretty damn good at the GMAT!
To help manage your nerves, you could try some visualization techniques. Imagine various test-day scenarios such as getting stuck on a question, issues in the testing center, feeling pressed for time, or worrying that you’re underperforming. As you feel your stress responses start to kick in when thinking about these things, practice pulling yourself together and visualize focusing on getting correct answers.
When taking the GMAT, the best way to deal with stress is to get busy answering the question in front of you, focusing completely on the task at hand so that you redirect all of that nervous energy and naturally calm down. In other words, you distract yourself with a goal. Just tell yourself that all that matters is getting the correct answer to the question in front of you, and then when you have finished that question, take the same attitude toward the next one. Focus on winning each “mini-battle” and you won't have time for anxiety. If you can win enough of those battles, you can win the GMAT war, right?
I wrote an article that provides some more detailed advice about
how to limit GMAT anxiety.
Please reach out with any further questions.