What temperature is the room you are sitting in, that you need a fan and to remove your shirt?
Just curious, as your house may be warm and not need heating yet to stay warm - my old house feels cold as soon as temperature outside drops below 15c.
Solid walls and no solar gain through West facing windows at this time of year. My daughter's house has a conservatory facing South and that makes her house so much warmer - no need for heating there.
That's why I'm curious about yours ........