I work in an open-plan office, at one of the 'edges' of the room. Nobody sits behind me, but the printers are immediately behind me, and people often walk past to get to the toilets or an adjacent meeting room.
When someone is standing behind me (usually at the printers, or having a chat with someone en route to the toilets), I start to get nervous and feel that they are all staring at my monitor and judging my work. In a rational sense I am not worried about this - it's just the feeling of it which is strongly distracting until they move away.
I have a phone on my desk which has a camera for video calling, and I often turn on the 'self-view' function. When I start getting nervous as above, I glance at the screen, and 90% of the time that solves my nervousness and I can immediately get on with my work.
However, some people have commented on it/asked why I always have the self-view on (I usually say something about how vain I am - which is trueish, half the time I look it's just to check how my hair is looking!). More significantly, my boss tends to lean over me and turn it off himself when he walks past. He hasn't told me not to use it, but it clearly bothers him for some reason.
I was thinking of getting a small mirror to put on my desk instead to serve the same purpose without looking as strange to my colleagues as the self-view on the phone. But I'm worried that since they don't like the self-view, they also won't like the mirror. I'm not keen to raise this with them as I think it's an irrational nervousness, and just a practical adjustment that's a bit tricky to explain without sounding suspicious or weird.
How normal or appropriate is it to keep a mirror on one's desk in a setting like this?
For reference: I'm in in finance, I've been at the company for ~6 months, in a fairly junior position, in the UK.