What kind of income did you have? You mentioned paying estimates so that sounds like you had self employment income. You will pay Self Employment tax (Scheduled SE) on a Net Profit of $400 or more on Schedule C in addition to regular income tax on it. You pay 15.3% SE tax on 92.35% of your Net Profit (If it is greater than $400). The 15.3% self employed SE Tax is to pay both the employer part and employee part of Social Security and Medicare. So you get social security credit for it when you retire.
The self employment tax is added on to the regular income tax on your taxable income. How much is the Net Profit on Schedule C? Plus if you owe over $1,000 you will have an underpayment penalty on line 38. Better review your tax return.
Before filing, You can preview the 1040 or print the whole return
https://ttlc.intuit.com/community/accessing/help/how-do-i-preview-my-turbotax-online-return-before-f...
