Revealing mistake: When we see Ian split, his two selves are supposed to be looking directly at each other but they're really both looking slightly to the right. It's hard to focus when there's really nothing there. (00:15:45)
Continuity mistake: When Clark lifts Lana back onto the bridge, from a shot from above, we see that Lana puts her left leg onto the bridge into a sitting position. They then cut to a different angle but now both her legs are still dangling and she eventually puts her right leg on the bridge first.
Continuity mistake: The shot with Ian pulling Lana out of the car shows the shadow cast on the bridge covering half the road. A few seconds later, after Chloe gets free of the Ian that has her, the shadows on the bridge are much shorter.
Continuity mistake: At the Talon during Chloe's interview with Ian, Ian holds the mug by its ear, but in the next shot Ian is no longer holding the mug by its ear but by the mug itself.
Factual error: When Ian throws the unconscious Chloe over the edge of the dam we see her falling down as Clark falls with her. However, Chloe's body position is unnatural for someone who is falling while unconscious. Her head/body is arched backwards when air resistance should have forced her body to become level/straight.
Continuity mistake: When Ian is dragging Lana towards the dam, his double can be seen in the background dragging Chloe. The double is on Chloe's right side pushing her. Cut to a close up as Chloe says "Ian you need help" but now the double is behind Chloe and is pulling her.
Continuity mistake: When Ian confronts Mr. Frankle about his grade, the teacher removes both his gloves and is about to raise his face protector. Cut to a different angle but now he has his right glove back on.
Answer: No, there is no such character in the comics. He's a "meteor-freak" like all the other baddies on the show. The sound has something to do with him vibrating his vocal cords very fast to create a high-pitched squeal.