Welcome to GMAT Club (belated) and sorry you have had to make this post.
Your scores seem very much below of what was to be expected based on the GMAT Prep and MGMAT.
I would just take it easy for a month and retake.... I would however, up the verbal and see if you can get it as high as you can since it comes easy for you.
As to the quant, I think it was a glitch. It happens sometimes (no, the test is not perfect). I have seen people score as much as 100 points higher by just watching movies for a month. So, do not get discouraged.
I would however, brush up some other aspects of your quant. A good book may be (if you covered the MGMAT), Kaplan Math Workbook
. It has not changed a whole lot in the last 5 years but it is a solid refresher that can help you spot a few holes within a week. The MGMAT has a few books but I do not recommend their advanced quant for you - it is too hard in my opinion and you need to build confidence rather than have that destroyed. (Watch out for the GMAT Club tests
- ignore the scores actually or otherwise, it may discourage you).
For now, take it easy for a few days. Don't ponder too much about it - it was a glitch. Nothing about you.
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