Other mistake: In the first scene with Randy telling Jamie Lee Curtis to turn around, the reflection in the TV never mirrors the actual position of Jamie Kennedy. (01:22:30)
Other mistake: Tumbling down the ditch with Dewey, you can see that Gale loses her red pumps. In the rest of the scene though she goes to Mr. Prescott's car first and then back towards the street without fetching her shoes back. (01:17:55)
Other mistake: During Tatum's murder we see some problems exacerbate. The killers are not supposed to be invulnerable and are wearing a cheap costume, but they receive hard hits (Tatum breaks two bottles of beer, one straight to the face) and they don't have a single scratch. When she is killed, nobody hears her scream and nobody else needed to grab a beer either. Furthermore, Ghostface has the garage door fully open, but without knowing who is on the other side, that is one room away from the others, goes by the mysteriously unlocked door to the inside of the house. And we see Billy (who should be the killer there, since Stu was at the party) join in coming from outside.
Other mistake: Randy answers the phone and receives the news that the principal has been killed and left to hang from the goalpost. He gets the call from the telephone by the TV, and he his head reaches about half the height of the TV. The hidden camera is on top of the VHS player, a shelf underneath the TV, but somewhat Gale and Kenny in the TV truck get a close-up of his mouth. (01:16:00)
Other mistake: When Stu brings Sidney's dad out in the kitchen, you can see behind him a September 1996 calendar. Earlier in the movie, the scenes inside Principal Arthur Himbry's office do show a September calendar, which is obviously the intent of the movie, but it's a September 1997 calendar.
Other mistake: Two police officers drag Billy Loomis out from the sheriff office across the station; the younger officer stares into the camera right before it cuts away. (00:34:40)
Answer: Characters in horror movies are notorious for not doing the most obvious things. It's most likely that she was scared and not thinking straight at receiving numerous threatening phone calls, particularly when she is threatened after hanging up on the killer.
Manky
Also, when she told the caller that she was "two seconds away from calling the police", his response was that they'd never make it in time. She also knew he was nearby as he made comments that indicated he could see her. She didn't know it was someone that knew her. She's a teenager and scared, so her judgement was clouded. She reached a point where she believed her only chance was to get away from him by either fighting him or getting out and hiding somewhere outside.
dewinela