Continuity mistake: In the scene where Hermione makes Harry stand up after his name has been retrieved from the Goblet of Fire, Ron continues to look straight ahead and has an emotionless expression for that shot. In the next shot when Harry is walking to Dumbledore, Ron's head is suddenly slightly down and moving up towards Harry, and a glare has appeared on his face.
Continuity mistake: When Cedric puts his name into the Goblet, you can see that his hair is wet on his fringe and stuck to his forehead in several clumps of hair. After he has stepped away from the Goblet, his hair has changed position. The clumps of hair are in different places and a gap has appeared. (00:28:00)
Continuity mistake: When Dumbledore rages on Harry and asks him if he put his name in the Goblet of Fire, he first only put his right hand on Harry's shoulder, but in the next shot his left hand also appears on the other shoulder.
Continuity mistake: When Harry is being told by Dumbledore that he's home, Dumbledore's hands change position instantly. (02:05:20)
Continuity mistake: On the Hogwarts Express, Harry's hair changes in level of scruffiness. In particular there is one bit that sticks out to the side on his left that keeps changing. (00:14:30)
Continuity mistake: When Mad-Eye is blasted by Dumbledore he flies back with his hands in the air and hits the wall. Camera cuts and now his arms are down and he hits the wall again. (02:09:45)
Continuity mistake: The numbers on the blackboard in Moody's lesson keep changing. (00:24:00)
Continuity mistake: During the first challenge, the arena/stadium is significantly smaller during the bird's eye view CGI scenes than the physical scene's interior shots.
Continuity mistake: Just after Harry says to Mad-Eye that he never mentioned the graveyard, there is one shot of Harry and his arm isn't cut or bloody. (02:08:20)
Continuity mistake: The way Dumbledore catches Krum's name from the Goblet changes instantly. (00:30:45)
Continuity mistake: When Barty Crouch Sr accuses Harry, Ron and Hermione of casting the Dark Mark, the way he holds his wand changes depending on the angle. (00:12:20)
Continuity mistake: The size of the paper that has Harry's name on is considerably smaller when Dumbledore gives it to Harry. (00:32:20)
Answer: Not at all. In fact, David Heyman made the decision for his eyes to be blue in the films for him to be more scary! They felt that his red eyes in Sorcerer's Stone did not show enough emotion to make him an evil character. It was felt in Goblet of Fire that the light blue eyes would be perfect to show his evil in the moonlight, and they kept it on for later films.