"Over/under" is a betting term; this is one of the few episodes that didn't share a name with a song at the time of release, though songs with similar titles were released after.
Jane shoots herself in the stomach at the end of season one. When she runs up to her apartment, and cleans up for Casey, she takes off her shirt to change and there is no bullet wound scar.
A police car cake is seen as the team first enters End Zone Cakes.