Definitely not! Many 12-year-olds are not tuned into test-taking and make little effort toward scoring well, because they see the test as unimportant. Have her take the test in subsequent years to determine whether this was an exceptional instance and encourage her to do her best. Her performance in school and her subsequent IQ scores will help you assess whether or not she has an average or better IQ. Even if her IQ scores are lower than average, she can achieve at above average levels if she brings tenacity and focus to whatever she wants to do. Life is more about passion and commitment than IQ.