The sheets thing sound like he is "nesting"(can't think of what to call it). We call it making their bed. Generally they do it and will throughout turn around 3 times. That's what all our dogs have done. I believe wolves do it too. The scratching on the leg thing sounds familar. Alex does that when he wants to get picked up. He has bad knees and he knows he shouldn't jump. So if he wants to get onto the bed or couch he will scratch for me to pick him up and put him on the bed. Or just to get picked up and carried around.
