Was 2:30 AM the time that... *SPOILER*

Was 2:30 AM supposed to be the time that Anna died? That's what time the clock stopped in the kitchen of her house, but I'm puzzled because it seems too late. If I were an attractive young woman, I don't think I'd want to be outside of my car at 2:30 AM changing a tire by myself. I'd call my husband or sit in the car (with doors locked) until a police officer or somebody came by. Also, if she left the message about having a drink with her friend at 6:07 PM, isn't 8 hours a little long to be out drinking? After 3 or 4 hours of drinking, I'm ready to go home, especially if I got up early that day. Who would even still have the energy to be out changing a tire at 2:30 AM the next morning if they had gotten up at 7 or 8 AM? Wouldn't she be too tipsy to change a tire, not to mention too tipsy to drive?!? This is not to pass judgment, but I'm confused because I would have thought she died several hours earlier than 2:30 AM.