At the end of the episode, there is a shot of Jonathan Kent's tombstone. The
date reads Sept. 1, 1954 - Jan. 26, 2006. (Jan. 26, 2006 is when the episode
Jonathan Kent died first aired.) But episode 6 of season 3, Clark sees the past
and Jonathan Kent's mother is pregnant with him, and the year is 1961.
When Suzanne Capra is talking to Clark she pushes her hair behind her shoulder to reveal her name tag. In the next shot when she gives Clark his name tag her hair is back in front of her shoulder and then behind it again in the next shot.
When Lois ushers Clark into the elevator, she pushes the up and down button at the same time. This wasn't a mistake. She was calling two elevators, one to go up and one to go down. She even says, "I'm going up, you're going down."