When Keith is running up to Janet on the sidewalk he passes a woman in a gray overcoat walking in the opposite direction. When Keith finally reaches Janet and stops to talk with her, the woman in the gray overcoat walks by him once again headed in the same direction as before.
In the last scene where Laurie shouts out the back door to Keith that he "can't go on running forever" (from the boyfriends of a bunch of school girls who have been chasing him), her hair is tied back. The previous shot shows her hair is loose.