My 6 month old Goldendoodle seems tired and has less energy than usual

[Samantha and Socrates]

This may be the product of a worrisome mommy, but my Doodle just seems a bit off. You probably wouldn't even notice if you didn't spend time with him like I do. He just doesn't have the energy level that he normally does. For example: when I let him out of his cage in the morning, he is usually raring to go - we have a routine where I let him out, he jumps on the bed with me and I scratch his tummy while he rolls around on his back and talks! He's wiggly and excited and wants to lick and jump up. This morning he trotted out of his cage calmly and got up on the bed and just sat there. He wasn't lethargic, he just wasn't excited. And he normally scarfs his breakfast up fast, this morning he kept coming over to me without finishing, I had to take him back over to his food. I didn't have to make him eat it, and he did finish it, but he has never, ever left food in his bowl before.
Do you think this is something I should be concerned about, or do Doodles have off-days just like us?

[Libby & Bentley]

maybe he's just having an off day..bentley has them ocasionally.

[Dan, Judi, & Timbow]

Timbow gets like that sometimes too. Do you go to work after this happens? Timbow acts depressed on days that we go to work (I only work half days, so he's not alone for long). Maybe he senses you leaving and is just sad. He'll probably be back to his normal self tonight. If you don't work, then I would just think it's an off day, but keep an eye on him just in case he's not feeling well. :)

[Jane, Guinness and Murphy]

Guinness is like this once in a while, but it is almost always if he's had a really busy day before. If he goes to Daycare, the next day he acts a little lazy. I kind of like these days, because he's more "cuddly" than usual. Normally it's a "quick cuddle" and then he wants to play.

[Karen, Jasper and Jackdoodle]

When a dog who's normally a good eater is disinterested in food, trust them. Never try to get them to eat if they don't want to, because if there is a situation brewing, like pancreatitis, (NOT saying that's what it is, just giving an example) eating can make it worse. A change in energy level plus a lack of appetite can very well indicate that something is wrong. Most likely just a tummy upset, but there's no way to know at this point.
Dogs don't have "off-days" just like us, because what causes us to have off-days if we aren't physically ill is moods and worries, and dogs don't have those...lucky things! So when a dog is "quiet" and lacks an appetite, those are indications of illness...especially in a 6 month old puppy. Although Judi's point that he may be depressed about you leaving for work is a good one, I think he would be doing that every day if that's what it is.
I would make food available but don't urge him to eat, and watch him. I hope he is fine and it turns out to be nothing.

[Leslie and Halas]

Is he losing teeth? When Halas was losing his baby teeth, he seemed to have a little less energy than normal.

[Samantha and Socrates]

UPDATE:
I think he may have had an upset tummy. (And he is losing teeth right now, so that may also have something to do with it). I watched him closely yesterday, and besides not being as excited as usual he was his regular self. He ate and drank just fine, he just seemed tired. We went for a walk in the afternoon and he went potty twice. I noticed it was less formed than usual, but not diarreha. Once he got that out of his system it was like he picked up speed! He started running and grabbing sticks - much more like his usual self. By evening he was back to bringing me all his toys and terrorizing the cat! And this morning he greeted me as usual and ate his breakfast like he was starving, so I think all is well.
Additional question - our home is pretty well puppy-proofed, so I know Socrates didn't eat anything serious. But have any of you noticed your Doodle's getting upset stomachs after eating certain things?

[Allyson, Peri & Taquito]

I vaguely remember some posts in "Puppy Madness" group about pups losing their teeth and acting a bit off. Try a search in there. I think this is normal. If he eats and drinks fine today, I would really not worry about it. For instance, my Peri has had sneezes and a cold for the past 2 weeks. Yes, I have brought her to the vet, but I never really worried because her appetite never left. That is the biggest cause for concern.

[Julie B.]

Since he is a puppy you may be giving him bones etc. to chew on? I have found that certain chew bones cause stomach problems... especially the rawhide variety. I don't give Luah those anymore. Did you give him a chew treat the day before?

[Jane, Guinness and Murphy]

Certain treats bother Guinness's stomach. The last time it happened, the Agility trainer was giving him her treats, and they did bother his stomach. He had a couple of very loose stools and even spit up a little. He didn't eat at all that night. The next day he was fine again. Since then, I'm really careful what treats I allow him to have. I'm not sure exactly what treat it was...something in a tube that she broke into pieces.