I think that it is tough to gauge what the drop was caused by without knowing a little more about your situation. Some common reasons people's scores will drop come test day include: fatigue (potentially caused by taking practice tests too close to the real exam), anxiety, and unfamiliarity with the format of the test.
Come round two, you will be familiar with all of the test procedures, which will also make you less nervous. Here is the approach that I recommend to my students in their preparation for the GMAT:
Focus on your shoring up your weaknesses (while still practicing your strengths, can't lose that) in the time leading up to the exam
In the last week or two, shift to focusing more on strengths and less on weaknesses (need to "secure your floor," as it is very important you capitalize on your strengths)
Do not take any practice tests in the 2 or 3 days prior to the exam. You may become fatigued if you do
The day before the exam study for 2 hours or so at most. Your work is done, so focus on relaxing and mentally preparing yourself
Test day do a couple of warmup problems, maybe 20 minutes worth. Then knock it out of the park!
I hope this helps!!!
Veritas Prep | GMAT Instructor
If you found this post helpful, please give me kudos!!!
Save $100 on Veritas Prep GMAT Courses And Admissions Consulting
Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options.
Veritas Prep Reviews