That's what I did originally...I don't even know how to upload more than one at a time...The gallery's log files do not show that you've uploaded anything.
Try uploading fewer pictures at a time. Alternatively, try uploading them one-by-one. Remember that each picture needs to be named and tagged after you have been told that the pictures have successfully been uploaded to the server. If you just click away that screen, they may not appear in the gallery and get discarded after you're logged out by the system.
So please try again. If the problem remains, report back!