Continuity mistake: When Jim and the other two characters are making their way to Jim's parents house, they are seen on the Docklands Light Railway track going towards a place called Island Gardens. The next shot shows them at a station called East India which is completely the other direction to where they were going down the track. Obviously, only users of the railway would pick up on such error though.
28 Days Later (2002)
Trailers
Directed by: Danny Boyle
Starring: Brendan Gleeson, Cillian Murphy, Christopher Eccleston, David Schneider, Alex Palmer, Bindu De Stoppani, Jukka Hiltunen
More trailers
More mistakes in 28 Days Later
Hannah: Are you trying to kill me?
Selena: No, sweetheart. I'm making you not care. Okay?
More trivia for 28 Days Later
Question: At the end we are left with the question of the pilot's intentions, and what happened. Is he going to help them, or pull an about-face and machine-gun them down thinking they're infected?
Answer: That question is actually answered. The pilot is speaking Finnish, and he says into the radio "lähetätkö helikopterin" which translates as "Can you please send a helicopter?" Looks like he was actually helping them after all, and there is still some civilization (or at least people with radios and helicopters).