Barney my 9 week old puppy prefers to sleep on the fire hearth (fire not lit) or the metal floor of his cage. He sometimes sleeps at my feet on the carpet but eventually wonders back to cooler fire hearth or kitchen floor (cold tiles) is this normal.
I think pups are slightly warmer than adult dogs (might be wrong! Have a vague recollection of reading something about pup and adult temps - but please fell free to correct me!) so he's probably cooling his tum!!!
Luna prefers to lie on cold slabs outside or the cold lino kitchen floor when hot, carpet or grass if not. See if his habits change as the weather chills more and more and more and more.........!!