So it turns out there was a piece of the old SD card still stuck inside the camera, which I was able to get out. Unfortunately, the 'ush to eject' mechanism seems to have been broken, so that the only way to keep the card inside the camera is by closing the door. The camera still works, but I think it's affected write times, a little bit. It's working, though, and I'm going to be in Pittsburgh in roughly three weeks, which I would really like to have my camera for, so I probably won't be sending it in for repairs until after I return.