Can this stupid mistake I made in Picasa 3 be corrected?

Warning: Techtard-ness ahead.

I was attempting to upload some photos from my camera, using my brand spanking new version of Picasa 3. I stupidly instructed the program to erase my camera’s memory card as part of the process. Once I saw that all of the pictures had been ‘acquired’, I (again, stupidly) thought the process was done. Unplugged the camera, clicked “return to library”, and went looking for the pictures I thought were already uploaded.

As you can probably guess, they aren’t on my computer. And they’re not on my camera. At least, not that I can find. To further complicate matters, shortly afterward we had the thunderstorm from hell break out directly over our house. As a result, I turned off my computer. Only much later did I see the little “upload” button at the bottom of the Picasa page, and realize that I never clicked on it.

Is there any way to recover these pictures? Could they be sitting in some file, waiting for further action? Or are they gone for good?

I’m using Windows XP, if that makes a difference.