Level 56
Are you using git or any other source control mechanism? If so try reverting to a previous commit.
$ git status # check which changes were made
$ git reset --hard HEAD # revert any changes not committed yet
If not, I am afraid there is not much to be done.
EDIT
Please execute git reset --hard HEADwith cautious, it will revert all your uncommitted changes .
If you need to revert just some files use:
$ git checkout -- /path/to/file
You can revert event deleted files before new commits