regardless of whether the $56K is adjusted gross income or taxable income, without self-employment income your tax would be about $8000 if the $56k is taxable income or about $5500 is adjusted gross income and you are taking the standard deduction. you need to review your return line by line and look for errors in data entry.
put another way for your tax to be over $14K filing as single your taxable income would need to be about $83 to $84K -50% more than what you say.
