Hi, my taxable Income, filing jointly with my spouse, is $14,488. And the TurboTax is states my Blended Tax Rate is 34.7%. Shouldn't it be only 12%?

Hi, my taxable Income, filing jointly with my spouse, is $14,488. And the TurboTax  states my Blended Tax Rate is 34.7%.
Shouldn't it be only 12%?