My dog, who is only 3 years old, has been moaning and groaning a lot recently. I can't figure out why he is doing this. I've read some other people say they have 10+ year old dogs who moan because of arthritis etc. but I've never heard of this in such a young dog. When he's lying down he moans sometimes for no apparent reason like, "ughhhhh I can't believe you're still practicing guitar" or on the computer or whatever. Also sometimes when I go to give him a hug he lets out a moan like, "ugh don't hug me." What's going on here. Is he just in a bad mood all the time? Is he sick or what? Someone give me some advice.