Hi Hasan,
... looks like you are up for some adventure here

- I assume you don't have a backup

- that of course would be the easiest.
- if the directories were links, then only the links are gone ... else

- if the latter is true: you can try some delete file recovery software such as
Recuva (which is free). However, since the Desktop is on your system disk and as you keep using your disk, you keep writing to it ... chances are that stuff gets overwritten (after all, the space has been freed, so Windows can use it to put eg. temporary files there ...); in any case, you should/must recover to another disk (eg. USB stick large enough to hold the stuff. Plus, count on some time to rebuild the directory stuff ...
- hence, if the stuff is
really important, shut down the computer and search for professional help (but that's $$$!)
Stefan