You can actually see the blood on his right hand as he goes to cup the sides of her face, previous to this you can see the blood pooling from her back and around her head, as he cups the sides of her face you can see another hand to the right of her face (his right, her left) looks like it might have something in it, back the video up and play it a couple of times and you realize it is actually her left hand with what looks like it might be a pen in it (which actually is blocked from her face by the guy cupping either side of her face), so no one dumped anything on her unless she did it herself or it happened before the video was shooting. (what I think, for what it's worth)
A relatively motionless person does not easily fake blood pouring from their nostrils.