Charlotte gets a nose bleed, Daniel is worried

As everyone starts heading back to the beach, Daniel notices Charlotte's nose is bleeding. This happened to George Minkowski before he died and it happened to Desmond before he contacting Penny as his constant. It seems she's having some "side effects" from the island. Daniel looks incredibly worried about Charlotte and clearly knows something, but doesn't tell her anything. This problem will undoubtedly get worse in the coming episodes.