Your withholding is applied to the taxes that you owe, but it is not your actual tax.  When your employer withholds money from the IRS, they are sending payments on behalf of you to the IRS (and your state if it has an income tax.) 

The purpose of the withholding is to ensure that the majority of your total tax due is paid on time.  The actual amount of your total annual tax isn't known until you complete your tax return.

After the end of the year, your W-2 shows your income, amount of tax already paid (withholding), and other items that factor into your total annual tax bill.

TurboTax helps to prepare your tax return. The tax return uses information such as your income, marital status, and number of dependents to determine the actual amount of your income tax.  It also reconciles the tax due with the payments (withholding) you have already made.  

If your withholding exceeds the amount of tax that is deemed to be your responsibility, a tax refund is sent to you.  If your withholding is less thank your total tax, then you are required to submit additional funds to cover the tax.  

"I owe some of the money I'm getting back" does not make sense.    Do you mean you expected to get everything you are seeing in box 2 as a refund?  It does not necessarily work that way.  Your tax liability is based on a combination of things including your filing status, your income tax bracket, your withholdings, your total income, etc.  Even having "0" as allowances on your W-4 may not be enough withholding for you to get it "all" back.