I think he's seriously bored. :-) Since he tail curls up when he's outside, there is obviously no injury. He spends way too much time being a couch potato and needs to get out of his territory. Having company all day is no substitute for regular outings.
Instead of playing for an hour, try taking him for a walk instead during that time. Take both dogs with you - it helps them both work together as a pack.
Too many times we forget that even small dogs are still... dogs! They have the same genetic needs as the bigger dogs, and that means walking out of their territory and smelling and marking new things. Give it a try. I think you'll be surprised at the results. :-)
Well he has always been happy and loving. He is about 4 years old. We did express his anal glands and that didn't seem to help. He still eats and is intrested in treats and playing.
His typical day starts with us taking him outside for potty time, then we go inside and play for about 15 mins and I give him a treat & fill his food bowl and I am off to work. He has company all day as I also have a great dane who is in love with him and he is with her. I come home, and it's potty time again and food time. We play for about an hour and I brush him and we cuddle and watch some TV. Then we go to bed (He sleeps in the bed with me and my Girlfriend).
I don't know what is wrong but he has been acting strange. It's mostly his tail which is always down when inside. Take him out and it curls right up!
That's interesting. I had a shepherd mix who curled her tail into a donut high over her back most of her life. She was a very dominate personality, and that got her into trouble when her behavior turned aggressive to other dogs and people outside her pack. Old Chica forced me to learn some dog psychology and I will thank her forever for giving me the chance to learn.
Once I took over the job of being the pack leader, Chica's tail relaxed to a normal position. In all those years I never knew that a tail held up high meant a whole lot more than looks. Tail position is just one part of a dog's body language.
First, if your pug hasn't had a vet exam in quite a while, take him in and have his anal glands checked - along with everything else! You need to rule out a physical problem first.
Assuming all is well physically, you'll need to start looking at behavior issues. It might be a simple case of boredom. Dogs NEED to be walked every day, and not only for the physical exercise. They need to get out of their territory for their mental health. That doesn't mean that he gets to drag you down the sidewalk and go wherever he wants. You have to be a calm and assertive leader and make it clear that he goes where YOU allow him to go.
Have you both ever been to training? If not, that's a great place to start for both you and your dob. Training is actually more about teaching humans how to effectively communicate with their dogs.
Can you give us more information on your pug's behavior in general, and what a typical day is like?