You can access your forms' submission data from the Dashboard.
If a form has at least one submission, a number will appear in the top-right corner of its thumbnail image. Click on this number to be taken straight to the Submissions page for that form.
Alternatively, if you click on the form's thumbnail image, you will see a menu appear with a few options. From here, you can select Submissions.
Finally, when viewing your forms in the List Layout, you can click the X Submissions button to see this page.
Note
If your submissions page is not up to date, you might just need to refresh the page to reload the submissions.