I took some money from my retirement fund last year. It was pre taxed 20 percent. Am i required to pay additional taxes on that money when i file my 2018 taxes?

[VolvoGirl]

FYI -you mean file your 2017 tax return.  We don’t do our 2018 tax return until 2019.

You didn't actually pay the tax or 10% penalty (you pay a 10% early withdrawal penalty if you are under 59 ½).  You had taxes withheld like from your paycheck. You still have to enter the whole gross original amount (before taxes were withheld) with your other income to figure out the total tax (and it may put you into a higher tax bracket) and then the withholding is subtracted from the total tax to figure your refund or tax due.  The withholding will show up on 1040 line 64 or 1040A line 40.  The 10% penalty is on 1040 line 59.

It has to break out and show the 10% penalty separately on your return and then you get credit for all the withholding taken out on Line 64.

And by increasing your income you may have lost some credits like the EIC .

And check if you have the right taxable amount showing up.  And it's on the right line.   A 401K is usually 100% taxable.  Check 1040 line 16b (1040A line 12b).