All the files that have been uploaded (or still in the process of uploading) in the current session can be accessed by clicking on the "Upload Activity" icon at the top left-hand side of the screen in the Data Manager page. Once you click on that icon, you can see all uploads and their progress. If you are uploading images, you can also decide to mark them to be processed once the upload is complete. In this case the system will automatically start the point cloud process upon the completion of uploading the images.
You can start processing point clouds out of your images while they are being uploaded (before the upload process finishes) by following the instructions here.