A capital loss is not part of the itemized deductions. Capital losses appear on Schedule D and then are carried to the front page of your 1040, line 13. Capital losses in excess of capital gains are limited to $3,000. If you have a negative amount on line 13 of you 1040, you received benefit for your capital loss carryover. Amounts not used this year are carried to next year.
Your standard deduction is $6,300 if you are single, $9,300 for head of household and $12,600 if you are married filing jointly. If your deductions are above the relevant standard deduction for your filing status a Schedule A will be generated and you can see the itemized expenses. If your expenses are below these amounts you will not have a Schedule A. You will be able to deduct either the standard deduction or the amount on Schedule A. The reason the $6570 is higher than you expected could be applicable deduction for sales taxes.
