I am looking for a movie about a person turning into a very strange monster, with a black vortex effect, had a red / pink eye instead of a head and had a mouth on the stomach that opened horizontally instead of vertically. I only remember a scene of a truck and a lorry driver who went behind the trailer to check what had happened, and then I remember talking to this person, who soon afterwards transformed into the creature described above, and the scene ended that the monster he had eaten it.