I did that very same stupid thing! I imagine lots of people will - the slots are just too close together and they are not visible from the side you are typically looking at. Oh, well, it is a BEAUTIFUL and powerful machine, just not quite perfect, yet!
My husband fished out the card for me. Here is what he did:
I took a sheet of cereal-box cardboard (about .4 mm thick and folded it in half vertically and then horizontally to get a quadruple thickness. From this I cut an "L" shape 13cm tall, 6.5 cm across the base, and about 1.7 cm wide, with the second fold along the tall back of the L and the first fold along the base. This way, the base tends to spread out somewhat. (Previous sweeps with single thicknesses of cardboard had failed to catch the SD card.) Compressing tip
of the base with my fingers, I inserted it high into the CD slot (unit unplugged, by the way), hooked it downward until it felt as if it hit the bottom of the slot, and dragged it outward. It pushed the SD card out. At no point was any noteworthy amount of force required.