Deliberate mistake: The Messerschmitts have painted yellow fronts, this wasn't done by the Germans until after Dunkirk. Christopher Nolan has admitted doing this deliberately so the audience could tell the difference between the Spitfire and the Messerschmitt during the combat scenes.
Deliberate mistake: The car's headlights are angled differently. After the car hit Pete, its headlights were angled upwards (more toward the sky than the road). This enabled a clearer view of Charlie when he approached and knelt next to Pete's head. A later, more distant view shows the headlights shining about waist-high, which would be more typical. (01:29:00 - 01:30:10)