In the flashback scene when Ben (as a child) knocks on the foreign exchange student's door to return her panties, she is shown with a towel wrapped around her head in the first shot, then with her wet blond hair hanging down (you can just see the ends) in the second shot, then in the third shot just when she is about to close the door the towel is back.
In the Zola Budd flashback scene the young Ben in shown watching the 1984 Olympics. This puts the year of Ben's birth in the mid to late 1970s which would make him late twenties/early thirties in the present, but the adult Ben is clearly portrayed as an undergraduate student of about twenty. The ages would be correct if the main body of the film was set in the mid 1990s but to accept that would involve too many anachronisms (references to texting, Sainsburys uniforms, cars in the car park, etc.).
At the beginning of the football match, Jenkins is wearing a shirt with the number 4 on the back. In at least one scene during the match, the shirt has a 5 on the back instead.
When Jenkins speaks on his cell phone in the middle of the football game, the sky is light, but in all the other shots the sky is dark.
When Sharon takes a bite of Ben's sandwich in the locker room, the bit of food is on her right cheek when she is seen from the front, but gone when she is viewed from her rear right.
In the scene where Ben stops time and starts to draw the naked girl in green you can see that she blinks, that should not be possible because time is standing still.
The Swedish exchange student's appendectomy scar also appears on one of the time-frozen supermarket shoppers.
At the end of the freezed supermarket scene, when Ben pulls down the woman's top she moves her left arm away from her body.
In the scene where Ben takes his manager away in a cart you can see that manager blinks in the last moment, that should not be possible because time is standing still.
The scene where Ben opens the door after takes his manager away in a cart, the door shouldn't be able to swing as the time is still standing still.
When Sharon is reading her invitation to the art gallery, it is shown with the non-existent date of 31st November.