I feel obligated to mention… Please be aware of your own demeanor. We might not notice that our own body language can be suspect, and elicit awkward body languages from others… especially if we are assuming the worst.
For example, I had a friend who would stare at people in public places. I would ask him why he was looking so intensely at something behind me. He would respond, about someone looking at him weird. I would look at my friend weird if I didn’t know him and he was looking at me that way. Usually it was just someone, sometimes a worker, who was casually glancing around while working and seeing someone staring at them with “hard” eyeballs.
One other issue… we tend to focus in on things. We might be distracted by the potential threat, when an actual threat is some place else. As an example, I’ve known a few people that would get irritated when driving because someone came close to cutting them off or passed closely to the car. However, it often distracted them (sometimes for a few minutes) from other dangers… even to the point of missing a stop sign or light.