Yes, if you have all of the 2014 tax documents, such as W-2's, 1099s, etc, you can amend it. If you used TurboTax, you will need to use the download version for the 2014 year to do the amended return. You can find that version here https://turbotax.intuit.com/personal-taxes/past-years-products/2014
You will need to prepare the return, print and then mail it to the address in the Instructions page of that return. Amended returns cannot be e-filed due to IRS regulation. They can take up to 16 weeks to be processed.
If you did not file your 2014 return with TurboTax, you can go here on the IRS website https://www.irs.gov/forms-pubs and print the 2014 forms to complete and mail.