To be frank, such situation dose need a data recovery tool, of course you can select a freeware
to have a try.
The link will show you such a free data recovery which is a very helpful tool to retrieve lost data caused by reasons like the one you met. I have tried it once, it is really convenient. Now that it is free why not have a try?
If this cannot help you then perhaps you may just leave it there and wait for some time to see if the pictures will show up. But do remember you cannot store any new data in it in which case the old data will be rewrite and then you will never find them back again.