Google Sheet Edit Link

Once a form has been submitted, Is it possible to click the edit link, make changes on the form and then submit it as a new submission so that I can compare results from the previous form to the updated edited version? 

No, edit link is for editing the submission made in your form. If you edit the submission and submit it then the changes you made will be saved in your submissions page and to google spreadsheet.

Let us know if you are referring to something else.