I accidentally deleted files from a mounted CF card. Where did they go?

TL;DR I deleted photos from a mounted CF memory card by accident, but they're not in the trash bin and the undo function did nothing. They're also not located on the memory card, which remains unformatted.

Details: I import photos in Lightroom by copying them from the CF card to my computer, however sometimes the settings seem to change on their own and Lightroom "adds" the files from their current location on the memory card. This requires me to remove the import and start again, specifying to "copy" the files. Well instead of "removing" the images I hit "delete" by accident. I realized my mistake immediately and it seems to have deleted them from the original source memory card. They're not present in the trash bin as far as I can tell. The trash hasn't been emptied and the card is not formatted. How can I recover these files?? Any help would be greatly appreciated.