The only way a taxpayer ends up owing taxes is if enough taxes were not deducted from their payroll throughout the year.  To learn more, please see the informational TurboTax video; Why Do I Owe The IRS.

Very likely it is not income tax but self employment tax that you are looking at.  If you have more than $400 of self -employment income (including most 1099-MISC) you have to pay about 15% of that.  But it's not income tax.  It's Social Security and Medicare.