Pay Check Woes

Commission-based jobs can be hard to live off of. I do know this, but I still had hope for my job with Our365. My hopes fizzled out today.
This is what happened. Every day I work, I set goals for myself on how much I think I can do in sales. A few weeks ago, I decided to shoot for a record $1000 in sales in one day. I walked out that day with sales of $982!! (the usual sales for a photographer at the hospital is any where from nothing to about $400, so that was a big feat). After that day, I just knew I could do the same the next day. The next day, I hit $650 in sales, but since it was a holiday, I, also, got hourly pay (so it came out to the same amount I had made the day before).
At this point, I was pumped, and excited to get my first BIG check. So, imagine my surprise when instead of getting a bigger check than normal, I got the same kind of check I always get!!! I was shorted over $500 on my check!!!
Of course, the check is not right, and it will have to be corrected by pay roll, but who knows how long that will take!!!
They have been asking me to pick up extra days, but I don't want to do that until I know I will get paid for them!!
It should make me feel better to know that I wasn't the only one whose check they messed up. The other 3 girls that work at my hospital were shorted, too. It doesn't make me feel better, though... I feel bad for all of us!!!