Just a reminder. You might want to check your exposure compensation setting. I had set my F801 to -2 stops exposure compensation for a spotlit stage performance several weeks ago. Of course I didn't notice that it was still set until I rewound the roll for processing. Luckily I did notice, because we are going on vacation in a week. Still lost about a half roll, I assume.
I'm kind of surprised the exposure compensation warning is as weak as it is. My pentax cameras flash LEDs in your face when it's on, on this thing there is just a tiny little flag on the main LCD.