The sitting on you thing, well, have you ever seen a litter of puppies interact? They crawl all over each other and sleep in a big pile o' puppies. It's just how dogs are.
Yelping under the bed is likely just attention seeking. It sounds like he gets rewarded just often enough for it to make doing it worthwhile. I bet if you ignored him entirely when he does that for a while, he'd stop.
As to his appetite, some dogs are self regulating with food. They eat enough not to be hungry and stop. (Then you have my dog, who would probably try to eat a 30 lb bag of food in one sitting.) If the dog is healthy, at a good weight, filled with energy, don't worry about it. If this were a new thing, then I'd say go to the vet, because changes in appetite are a huge red flag for illness, but it sounds like he's always been that way. https://www.animalpicturesociety.com/boxer-dog-1877 As for doggie stuff my dog does, whenever we go upstairs (upstairs is carpeted, downstairs is hardwood), Kabota throws himself on the floor and starts worming around and growling and barking. He'll do this for a minute or two, stop abruptly, and walk away like nothing ever happened. No idea. None at all.
