I took Dylan for a walk this morning and he was in and out of the river. He was absolutely fine. When we got home, he lay down in the hall and I later heard him winging. There is something wrong and I just can't work out what. Every few minutes he goes mad and flies around in circles really distressed. He won't get up if I call him, and if he does then he is in great distress. It seems to be centred on one of his front paws, but I've checked it and can't find anything wrong. I've checked his pad and when I press or manipulate the paw and leg it doesn't seem to hurt him. I've checked his ears and all his body and can't find anything wrong. Any suggestions please??