people with a smell they don't have

I wonder if anyone else have smelled a different kind of smell you know the other person/s not to have? It has happened to me in childhood with some people and then too, weird enough, with an ex. He to me smelled badly, lots of sweat when I knew that was not his smell. He came to smell this way at our first meeting and now and then continuously, very strong smell, and I could see he was fresh and clean and would smell good. Years later did a past life regression and got a glimpse of him from then a possible past life and in that scene he was smelly, sweaty and up to something bad, but caught. Another time, to use another example of another person, it had a very specific hospital smell way back in time.

-Am I able to smell something that is not real anymore but used to be, stretching as far as from a past life?

-Or what is this?