TextEdit document disappearing?

(Please move this if it is in the wrong forum).

I tried to open a saved TextEdit file today. I had previously opened and saved it 2 days ago. But today when I attempted to open it, the icon was there for a few moments and then disappeared. This has happened one other time over a year ago.

Anyone know why this is happening and what I can do to retrieve the file? I work from home online - and the file that disappeared is my timesheet. Luckily I have the times already entered into the online database - I just would really like to know how to fix this so it doesn't happen again.

My operating system is OSX 10.4.11
Please let me know if you need other info about it. TIA for any help offered!

I'd say it's unlikely anyone knows why that's happening.

More info? I'll say!
Where was the icon before it disappeared?

In a folder? (which one) In your Dock? On your Desktop? etc.

Okay - more info (sorry, I'm not very computer savvy when it comes tot he technical stuff). The file was in a folder that is located on my desktop. I only have 4 folders on my desktop, and had accessed that particular file 2 days prior, and was able to close it without any problems (my computer didn't freeze up while it was open, or anything like that). I haven't moved the file or folder around at all, and know I didn't delete it by mistake - I always check what's in my trash before emptying it.

Please let me know what other information will help. Thanks!!