Not Too Bad
The camera work was a bit shaky. I have a feeling you were going for a a shakey camera, but it was very tough to watch with it moving around like that.
The flash mouths were pretty bad though. You should do clay mouths.
The Flash as a whole wasn't bad though. It was somewhat entertaining and I was wanting to know what it was that was hunting them so it kept me wanting to see it.
Pretty good though. Keep learning and good luck.