Never using again

I was just finishing up a 12 minute, yes 12 minute video (about 3 hours of raw footage to edit) and It blacks out, never happened before. I re-open, and ALL OF MY AUDIO FILES ARE SHIFTED. And all of my CUTS ARE CHOPPY AND CORRUPTED now. I have never been so frustrated in my life. Now, what was my hard work, has been completely wasted, and my video will never be uploaded. Im so disappointed. Also, ive never had more trouble with something as simple as downloading an audio file from YouTube to use for sound effects since iMovie has NO USEFUL EFFECTS WHATSOEVER.

KD FILMS about iMovie, v2.2.3