The growling and shaking things does sound like puppy play - our pup is nearly a year old now, but still likes to do this - we have the sort of toys where she can grab onto one end and we hold the other, and she growls and shakes, and we play tug of war. Apparently you have to make sure you always win tug of war, though - so the puppy doesn't think they are top dog over you - but Coco wins sometimes and it doesn't seem to be a huge problem.
She's a brown lab puppy, by the way, and I came over all mushy at the photo of Elsie's litter on your profile pics, Slubber - soooo cute, and she is absolutely gorgeous!
We haven't bothered too much with specific dog bedding - she's got a soft pad in her cage, and we cover it up with fleecy throws and towels, which are nice and easy to change and wash regularly.
The biting and mouthing definitely settles down as the puppy gets older - Coco is much better now, though one of her favourite games is to take dh's socks off, and then try to remove the flesh-coloured 'sock' underneath, which is a tad painful.
Labs are lovely to train, because they love their food and are very food motivated. But this does mean that as they grow, they can become terrible theives. So far, in her short life, Coco has eaten 15 mince pies, one mars bar, a pound of defrosting bacon, three steaks, three salmon steaks, a rum and raisin doughnut, some of a profiterole cake, two tiger loaves, three packs of butter, rabbit poo, sheep poo, horse poo, cow poo and her own poo, my glasses, a wooden cat ornament, several fence panels (in an attempt to get to the Love of her Life - the labradoodle next door), the post, the newspaper, several of my shoes, dh's wellies (thank heaven we didn't manage to find the Hunter wellies he wanted for Christmas and settled for a £10 pair from B&Q) and a whole pack of the tablets that are supposed to stop their wee turning the grass brown. There may be more, but I have forgotten!
All that said, we wouldn't be without her and she is such lovely company. Come the autumn, we will be able to enjoy my favourite walk, where she wiffles round in the undergrowth, and I pick blackberries.