We brought our puppy home on Tuesday and he was the usual ball of energy and curiosity. This morning he’s very lethargic. He doesn’t want to play or even walk around. Although he did eat a bit of breakfast and have twp regular looking bowel movements, he mostly just wants to lay down and sleep.
We’ll be taking him to the vet this afternoon as well as talking to the folks we bought him from.
First impressions: what could be wrong?
Please keep us posted. Little babies at that age are very fragile. 
Good news. Ricky is perky again. :bravo: I was wrong when I said he had regular bowel movements. They were a bit loose, which makes me think he had a tummy ache. By 1:00 pm my daughters reported to me that he was jumping around and chasing them up and down the hall. We’re keeping him away from other animals until he’s had his 2nd set of shots and gets just a bit bigger.
He’s a pure bread dog that was bred in Taiwan. That alone is VERY problematic as a rule of thumb. Fingers crossed for Ricky… Glad he’s doing better. 
Be careful you don’t overfeed because that causes loose stool and lethargy in some cases.
marboulette
Our then 12 wk old puppy also appear to show the same “symptoms” as yours when we first got her home for the first time. She even had diarrhea and what appears to be a little blood in her stool. We took her to the vet and the vet checked her stool and gave her a once over and said she’s fine. We’re chalking that up to stress as we had to drive her 1.5hrs back home from the adoption agency and new environment.
She is now 13 wks and doing fine! Even mischievous.
What happens with puppies is they do not have the proper bacteria in their digestive tract(too much of the bad bacteria and not enough of the necessary bacteria) to properly digest much food yet, meanwhile they have more appetite than their system can handle smoothly. It causes diarrhea, mucus in the stool, inflammation and even bleeding in many cases. Most pups get over that on their own, but a vet may prescribe a drug that will help reducing the amount of bacteria in their digestive tract.
The best way to avoid unnecessary vet visits is to feed little at the time but more often throughout the day. As they get through the first few months, you increase the amount of food while decreasing the feeding frequency. At two month old, a pup should be fed a little 4-5 times daily. By three month old, three times daily is enough and by 4-5 month old, twice a day is fine. Once a dog reaches 8 month old, one good meal per day is enough, although most people feed twice daily which is also fine, IMO.
marboulette
My dog is 2 years old and she likes to eat 100 times a day… although I only try to feed her once a day to control her need to poo…
I have read that dogs like mine (West Highland White Terrier) go usually by the nickname of vacuum cleaners… mine has a particular taste on mopping the floor of the kitchen and living with her tongue… and she is in a permanent state of “I want food”…
Ricky is getting 3 small meals a day although he id constantly wanting more. Every time we walk into the kitchen he sits by his bowl waiting. With the advice here we may consider decreasing the amount and increasing to 4 meals. So far all is going well, except for that one scare.