My mothers dog was scratching a lot and rubbing her tummy on the floor.
It turned out that her stomach and gut were very painful and inflamed. This was due to my Mother feeding her totally the wrong food. Fillet Steak, roast duck and roast lamb.. but that is another story !!
A change of food and a short course of tablets sorted it.. but at the time her behaviour was very strange..
Maybe a check up the vets might be best for you..
Janey, if I scratched and rubbed my belly on the floor, do you think she'd feed me steak etc?
------------- Some days you are the dog,
some days you are the tree.
Does he also wander around aimlessly or walk into corners? This and the things you mention can be onset of doggy dementia. Our JR began like this.
Mind you we also have two happy healthy dogs here that both scrat at beds before settling sometimes.