"I Should Have Known Better" is a song composed by John Lennon (credited to LennonâMcCartney), and originally released by The Beatles on the United Kingdom version of A Hard Day's Night, their soundtrack for the film of the same name.
The song is performed in the train compartment scene of A Hard Day's Night. It was in fact filmed in a van, with crew members rocking the vehicle to fake the action of a train in motion.