She is having a hard time feeling safe in almost all situations.
Explanation:
The best that describes Dicey’s mood is: "She is having a hard time feeling safe in almost all situations".
From the excerpt, we can see that Dicey was really having a hard time feeling safe. She seems to be nervous and disturbed. Her imaginations were not settled - she seems to imagine that the car was flying down the highway. I believe it was her imaginations that made her feel that faces might appear in the windows of the car at any time to ask angry questions.