I have a six month old shiatsu, which is a wonderful and fun puppy, in the past month he now wakes me up at 3am and 5am. Not sure why he has decided to do this. I have had raised dogs in the past and don't recall them doing this. This is a first for me. What can I do to prevent him from waking me up during the middle of the night? I have taken him for walks and tried tiring him out, did not seem to work