If you hadn't saved the song at all, try File > Restore Version to try to recover what may be an auto-saved version backup from the History folder.
As to the recordings: If your computer locks up, crashes, etc, while recording, the audio files may still be valid and usable. Once you reboot and open the song and locate the files in the song folder and drop the into Studio One and (if they import successfully, if the files are not corrupted because they were writing during the crash) and "Move To Origin" to move them to their original start location.
Studio One time stamps it's audio recordings in the file header so that information would still be there, if the files are valid.
