Unless you are able to claim certain credits and deductions on your tax return, your age and educational level does not determine the amount of tax that you owe.

If you claimed "exempt" from any income tax withholding, then your employer did not take out any taxes. This means that you become liable for the taxes at the end of the year.

If taxes were withheld, and you made more than the standard deduction of $2,215 for Single filers claiming less than three (3) allowances for Oregon, then you may not have had enough taxes withheld from your pay.

Oregon has a personal income tax usually ranking in the top 10 percent of the nation. It is suggested that you review your Form W-2 boxes 16, 17, 18, 19 to determine if the wages and taxes are correct. (Note boxes 18, and 19 may not be applicable.) 

You will then review the Form W-2 information you entered in TurboTax to ensure the amounts were input correctly. If they were, then more than likely you are responsible for the tax.