Accidentally Overwrote An Important File

Hello;

I've done something very stupid. I had a file open and went to open another very important file. I didn't realize that instead of clicking on "Open" I clicked on "Save As" and when the dialog box opened, I was in a hurry and simply clicked "Yes". This overwrote the important file I was trying to open with the file I already had open. Is there a way to undo this? If so...how?

Thank you all in advance for your time.

Recover an earlier version of an Office (2010) file

Thank you for the information, Ben. I tried to recover as you said. I did save the file when I made this terrible mistake. When I click on File>info there are no versions available. I click on manage versions to recover unsaved workbooks and there is nothing there. I am beside myself. I even tried restoring my computer to a previous save point and that did not work because all the excel reports are on a mobile hard drive which when I started using it a year and a half ago, I neglected to make part of the restore point in my system. Is there anything else that I can try?

Hm... this isn't really an excel problem anymore, so much as an OS/file management problem. What OS are you running? Windows 7 or something?

Anyway:
Recover overwritten files

The same procedure, with more screencaps

I'm using Windows 8

I apologize to everyone especially those that have tried to help me. I'm so upset over this, I'm not even thinking correctly. We're NOT using Office 2010 like I originally stated. We stopped using that a while ago. We are using Office 14. Don't know if that makes a difference...but I hope so.

Newdoverman: If it IS in the cloud, it would have had to go there automatically. I have no idea how to get it from there if it is there.
FDibbins: Unfortunately, we're a small "mom and pop" contracting company. My computer is the only computer in the office with the information.

I just can't believe that I was in such a hurry, that I neglected to read the dialog box. I KNOW better than that! What I overwrote was our project profit/loss file. Thank God it wasn't the book keeping file...but still, it has all the information on our projects as far as profit, loss and current stage. I have an old version from about a year ago, but there will be a lot of projects missing from that one.