My youngest Apollo was very laid back. He would go into playful spurts the first 6-7 months, but then go lay down or sleep. He gave me a lot of problems with the crate, he didn't want anything to do with that and was out of the crate at 5 months(before that he was in there minimally to begin with). He did eat, never super fast. In class he was very quiet and observant and took treats. It was at 6-7 months that he came out of his shell. He realized what a ball was and hasn't stopped playing since. He will be two in a couple weeks and he just started barking when someone knocks on the door or if he hears someone/something on the back of the property. I thought he would never bark, but he has a very nice big boy bark. At first I worried about him a little bit, but I was waiting for that puppy to come out and if finally did. Never went through a biting stage, a chewing stage, nothing most puppies do. He was a real easy pup(except our argument over the crate which he won). If you feel something isn't right, take him to the vet for a check up, xrays, and bloodwork to ease your mind.
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD