Data loss randomly



I was working on a file and C9 deleted the file. I do not understand how this is even possible, but it happen. How can I get this file back. I would really appreciate it if someone could help me out.
Replay of the scenario:
Was typing some php code, went to test and results showed.
Changed some code, saved and file was then deleted.
End of the scenario.
If someone could help me recover this file, I would greatly appreciate it. Thanks in advance.