I hate to be picky here, but you have bullets still in their casings flying at her. That's not how bullets work. Only the tip of the bullet is ejected from the gun, not the entire thing casing and all.
Obviously the bullets are being fired by some kind rail gun, and probably have some kind of explosive payload. Supergirl is pulling out the explosive payload, defusing it, and tossing the remaining shell casings. (The shells look like brass but there is either a good hunk of magnetic metal inside them -or- it's not brass.)
You can see one she's defused in her hands (and it looks like a full one in her mouth), and some of the "empties" falling down around. The one in flight, you can clearly see the round head tip of the bullet, but it's not there on the ones that are falling down to the ground. Which means they've been removed somewhere in between being fired and falling to the ground. And if they'd simply hit her at speed, they'd have crumpled on impact.
You can see one she's defused in her hands (and it looks like a full one in her mouth), and some of the "empties" falling down around. The one in flight, you can clearly see the round head tip of the bullet, but it's not there on the ones that are falling down to the ground. Which means they've been removed somewhere in between being fired and falling to the ground. And if they'd simply hit her at speed, they'd have crumpled on impact.
I am glad I didn't have to say it, it's an awesome piece non the less but I have to admit it was what took me away from the rest I startedby looking the one on her mouth I have seen this mistake done by people even in animation, the art it's great I'm not goin to take that away but just like GeekVarietyDotCom said not to be picky but eeeeeerrrmmmn.