During the night that Tree locks herself in her room, she approaches the TV and the clock shows the time as 9:24. The camera changes angles, and when it shows the same shot again - it now shows 9:31. It changes shots and returns once more and shows 9:24 again.
While running around the hospital in her gown, Tree's pink booties disappear when she enters the office, only to reappear when she runs down the stairs.
Trees smudged eye-makeup seems to change back and forth multiple times after she wakes up, although she does not have the time or opportunity to fix it.
When Carter spills chocolate milk on Tree on the second day, the position and amount of milk on her shirt changes between shots.
Tree, on one of the resets, takes a passerby's sunglasses and puts them on. when she enters he sorority house the sunglasses are gone,
Corky's Restaurant, a chain endemic to California, appears in Louisiana.
The killer breaks the driver's side window when Tree is trying to drive away. But the trooper who stops her for speeding doesn't seem to notice the window had been broken out.
When the newsflash about John Tombs is first shown, Tomb's first name is shown on the television as Joseph.
When Tree is attempting to elude the masked killer in the hospital parking garage, she flees in Gregory's silver Mercedes-Benz, using a floor mounted shifter, which that model does not have. In the US all Mercedes-Benz models come standard with a steering column mounted shifter.
In the parking deck scene where the protagonist is attacked inside a Mercedes-Benz sedan, she is shown using a console floor shifter. Most C/E class sedans after 2008 use a steering column mounted electronic selector stalk.
Tree tells the security guard that she has died sixteen times. Though she had only been shown dying nine times at that point in the film, the other deaths would have happened off-screen.
When Tree is in her hospital room, there is a rack by the door containing three boxes of latex gloves, all size (S)mall. A real hospital room always stocks three different sizes of gloves: (S)mall, (M)edium and (L)arge, because one size of gloves does not fit all hands.
When the police car is sideswiped, the black Charger shows no driver's-side damage, when there should be visible scrapes at the very least. As the fire starts in the police car, gas is bubbling up around the fuel door - gas won't bubble up like that and even if it did, the gas cap would be in the way.
When Tree wakes up for the last time, you can see a camera lens and matte box pulling away from her in the bottom-left corner of the screen as she sits up in bed.
Carter tells Tree that he brought her to his room because he was afraid that she might choke on her own vomit like Janis Joplin. Joplin actually died from a heroin overdose, possibly exacerbated by alcohol.