Not understanding how I feel? - Part 2; What others interpret

I was just wondering if anyone else has had similar experiences?

Whilst at work this afternoon a coleague asked how I was and said I look miserable, whilst I was waiting for a coffee. I was just feeling normal. So I just said I was fine, bit tired and needing some caffine. The coleague is newish and doesnt know me well, he seems like a nice friendly guy.

In another job, I can remember someone saying I looked miserable and unaproachable. It seems to be a reoccuring theme.

Im now not sure if this is "anxeity" and I just don't recognise it. I just don't really understand feelings in someways.