When Dean kills a vampire, blood is sprayed on his face, mostly on his right cheek. In the next shot the pattern is different, and notably the right cheek is almost clean. Furthermore, his mouth was agape when he made the kill, risking the blood getting into his mouth and turning him into a vampire. While the brothers didn't yet know how a vampire is made at that point, Gordon did and should have been alarmed that Dean might have gotten some of the blood in his mouth.
After Gordon cuts Sam's arm, two drops of blood fall onto Lenore's face. When Sam later helps her up, his blood is gone from her face.
Sam and Dean go to the Candler County Hospital in Red Lodge, MT. Red Lodge is the county seat of Carbon County, and there is no Candler County in Montana.