When Julia researches on the decapitated girl in the cafe, the date on her laptop changes from Tuesday to Wednesday between shots.
When Julia sees the Watcher and begins to follow him around town, approximately at the 51 minute mark, it starts to rain, to the point where the Watcher covers his head. Julia continues observing him while standing outside in the rain, and her hair remains dry throughout.
Julia's neck is slashed on the left side, but when she crawls away she is holding her neck on the right side.
In the beginning of the movie the main character has wavy hair but on scene later when she enters the room her hair is quite straight.
In a scene the woman has dark eyebrows just after that she has brown ones.