I do.

As soon as I find myself on my own or doing any task I'm well used to and that doesn't require much attention... I start obsessing about things, past and present.

Those things you mentioned, when walking... well, you know that there is a real chance that one of those things might happen to any of us and it's always a good thing to watch out for yourself, but I think that we tend to overestimate those chances actually. Big media corporations make a living out of amplifying bad news and make everything look like as if we are surrounded and it's gonna happen to us too...

It also annoys me when people are walking behind me and I can hear them footsteps, it makes me really go full blown paranoia mode, so what I do is just stop, turn around, pretend that I'm looking at my phone or something and let them go past.

I always keep a watchful eye on them though, because you just never know...