Q: iphoto problem: can't stop import

i copied a movie from an SD card, played the copy on my mac book pro to ensure it was ok, and then tried to delete the original on my sd card.  while it looked like i'd done that, when i tried to eject the sd card, i got an error message saying the file was still in use.  the sd card was greyed, so it looks like it had started the eject process, but stopped when it saw the file was still in use.

then i noticed i-photo was open, and it was saying it was trying to import a photo.  i've been trying to abort this for an hour now.  it finally displayed a folder that was labeled Import with a finishing import... description on the left, and a Stop Import button on the right.  when i click stop import, my mac gives a quiet ping.  i can't quit or close i-photo (pop up error window:  photos are being imported to the photo library.  please wait for import to complete.  only option is ok). 

i can't shut down my mac (same error message...i'm importing photos!).  in fact, i got another pop up window that said the application iphoto canceled shut down.  to try again, quit iphoto and choose apple menu > shut down!!!

i need to go home, but i can't shut down my mac.  how can i stop this import &/or force a quit from i-photo???