I try not to reveal I feel anxiety just because a black man has walked up behind me in a gas station in a bad neighborhood and he does not have a car. (Para. 10)
Meaning: I try not to show that I feel worried just because a black man has walked up behind me in a gas station in a bad neighborhood and because he does not have a car.
"A bad neighborhood" here means a neighborhood with a bad name because of
the frequent happening of crime or violence.