Other mistake: When the two gents are fighting in the restaurant Hugh Grant tackles the guy through the plate glass window and they land on the street. Two points: 1) How do they not receive any cuts from landing on shattered plate glass. 2) Check out the glass laying on the street. It is cloudy, a main characteristic of breakaway stunt glass.
Other mistake: When Bridget's friends come over to her home they always need to call up first. She then can buzz them in by pressing a button that unlocks the building's main door. Yet when Bridget first runs from her flat after Mark with just her bare feet you can hear her feet crunching on snow. She then runs back inside to put on her shoes and a sweater. If she really needed to buzz her friends in then there should have been a hallway where she ran first and not the outside directly. [As an addition: when Mark comes to Bridget's door to show her the newspaper article, as he says ...'I may have come at a bad time...' you can see a hallway behind him. When she runs outside at the end of the movie there is, for some reason, a different set outside her doorway. For example, when Bridget opens the door to run after Mark, it looks like she is running into bright sunlight - lighting way too bright for hallway illumination and especially out of sync with the evening sky.]