its quite easy to imagine in my opinion.
she drives home and gets these notifications, which clearly spook her, which is why she made extra turns etc.
she sends a few messages to friends and/or family, because she's freaking out about it, but goes to sleep because she doesn't know what to do
one of these friends or family comes by in the morning, sees her car and checks it out before ringing her door bell
the given facts are quite believeable, though i doubt there is a human trafficing relation which she seems to think. its more likely a potential stalker, upset boyfriend or similar.