Hey Ashim,
First off, let me echo Nicole's sentiments and remind you to take your time! The authors of the GMAT are terrific at knowing the mistakes that people tend to make while thinking too quickly, and they'll take you to task on those.
With that, I'd say that this first test gives you a great opportunity - go back and jot down a few notes on each of the "silly" mistakes that you made. You'll probably find a pattern with some common errors that you make often, such as:
Assumptions - assuming that a variable represents a positive number, or an integer, when that's not specified
Answering the wrong question - submitting as your answer the value for 'x' when the question asks for 'y'
If you're just aware of a few mistakes that you commonly make, you can use that "slow down" time effectively as you double-check for those recurring errors and save yourself from a handful of easy-to-make mistakes.
One last thing - like you predicted I wouldn't consider that test to be in any way an indicator of your ability or potential. But it's still not a bad idea to take a practice test early on so that you have some concrete understanding of the test, its question types, etc. while you study. It's easier to practice when you've seen a "game" situation and have some tangible goals.
Brian Galvin
GMAT Instructor
Chief Academic Officer
Veritas Prep
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