Here's what the founder of beatthegmat said in one of his previous posts
https://www.beatthegmat.com/test-anxiety-t207.html
"Another thing to consider: the GMAT isn't that important. A high GMAT score or a low GMAT score will not determine your MBA admissions. Also, try to consider the bigger picture--in your life, which is full of friends, family, and interests, is the GMAT really that important? I hope the answer is 'no' for you. Keeping perspective will help you with anxiety. If you think you are going to panic during the test, remember the big picture. "
So let's look at the facts. You're already averaging around a 670 which is pretty good. What happens if the GMATPREP test says you have a 650? Not much. How much of a difference does it make if you start averaging a 690 and then on the test you get a 670? Very little.
Also, whenever you take a test you need to take it with a grain of salt because there is a luck factor.
Thirdly, most of the time progress on practice tests isn't linear. You get one score of 650 then you get one of 700 then the following is a 670 and so on. What really happens is that your average over time will increase and that's what matters, and the most likely way for that average to continue to increase is for you to continue working and taking tests.
Cheers!
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