I'm the one who originally commented about the taste of metal or blood like getting punched in the nose as a sign of a concussion. But, both are immediately after the impact.

Anxiety can cause a myriad of false sensations. A past sensation of metallic taste or blood taste after a concussion can return like a flashback even though there is not true sensation.

I was going through the mail the other day and a flyer showed a giant pizza cookie offered by Pizza hut. As I said to myself, that looks good, I thought I could smell fresh baked cookies. And, no, this was not a scented flyer. I smelled chocolate chip cookies. When I looked closer, the picture was a peanut butter cookie.

So, yes, the mind can do strange things. Especially when one does not make conscious thoughts to correct erroneous and illogical thoughts.