Images and files that you've uploaded to any content can be managed in the Files menu link under Content from the control panel.
In this page you will see all file types you have previously uploaded. This page shows you its original name, the size of the file, when it was uploaded, and where it exists on your site. You also have the option of editing or deleting these files.
Another way to search for a specific file is to enter in the name of it in the search bar, sort by date or size of the file, choose the order, and hit "Apply".
In the top right corner you will see another tab, the "Private Files" tab where you can go to view and manage your private files as well as upload more.