How can I find a form I've already completed?

I am not sure if you are looking find the form you have created or the submissions when the form is submitted. 

You can always you view your forms in MyForms section of your account. However, when I look at your account there are not forms created at the moment. Let us know if you have any issues getting started with Jotform.

You can view form submissions as explained in the following article. https://www.jotform.com/help/269-How-to-View-Form-Submissions

I hope this helps. Feel free to get in touch.