Continuity mistake: The hammer on Leela's blaster changes from smoothly curved to angular.
Continuity mistake: As Bender is stomping to stuff the whale down the sewer, when the rope gets to the pavement, the top where the cover is tied suddenly jumps from the level of Bender's head to below the spot where his legs and body meet.
Where the Buggalo Roam - S4-E6
Continuity mistake: When Kiff is being offered the peace pipe, in one angle there is smoke coming out of it, in another there is no smoke.
Continuity mistake: When Bender laments that he'll be drifting through space with just a little swag, he takes a gold wristwatch out of the bag and puts it on. The watch disappears a few seconds later when he pulls the little piano out of his chest storage and is never seen again.
Continuity mistake: When Bender hits the asteroids, one pierces his head. Seconds later that asteroid is gone. Where did it go?
Continuity mistake: Near the end, when Leela talks to the second female blurnsball player, her black nose-stripe disappears then reappears throughout the shots.
Where No Fan Has Gone Before - S4-E12
Continuity mistake: When the Planet Express Ship first lands on the planet, it crashes with noticeable damage. When they try to sneakily escape while the screen play is going on (before they get the parts from the Star Trek ship), the damage is repaired.
Answer: Yes Leela knew from early on that Fry had feelings for her. They were pretending to be a couple in 'A Flight to Remember' from season 1 and Fry tried to get on dates with Leela ever since. She just didn't show signs of the feelings maybe being mutual before some of the later episodes.
Andreas[DK]