stuck in iPhoto

I was trying to import my pics from my iPhone to Mac Air ...it started importing and then it stopped after about a 1000 (I have total 1400ish)...and it's stuck...I unplugged my iPhone...and tried to exit the app but it won't let me close...it says please wait while your pictures are being imported! I even tried to restart my computer but it won't let me and says the same thing...I am stuck! what should I do?