Mine still acted like a 6 month old puppy when he was 13 years old! He only took a turn at 14 when he developed the "doggie Alzheimer's". He would go outside and forget why he went out. Sometimes he would jump up during the night and bark, and yet he rarely barked (unless he wanted water or food).
If a burglar would have come in, he would have greeted him with kisses. He thought everyone came just to see him. Where did you get yours?
Classifieds puppy. Got him on the day the ad first ran. You have to be careful though. There are a lot of scammers out there. The only places I would never consider are pet stores & people who sell several different breeds because they're usually puppy mills.