Audacity projects have a matching AUP file and a _DATA folder. The AUP file is the show manager and tells Audacity how to use the work inside the _DATA folder. Sometimes you can save a damaged simple recording with the recovery tools and without the AUP file.
If you overwrote the project (the project with the same name was in the same folder as the old project) then you cannot retrieve the old project.
What version of Audacity are you using (look at Help > About Audacity)? Any version of Audacity from the last few years won’t allow you to overwrite another saved project.
Gale,
My immediate reaction on reading that statement was: oh yes it will! I use v2.0.2 and, when assembling a soundtrack, regularly do File > Save Project. Audacity always overwrites what was previously there, and I do not receive any warning message. Please note: I understand the risks of working this way and accept those risks. So, could you please clarify what you meant by that statement?
PeterA