Nose temperature does not indicate puppy’s health. You should take body temperature (rectal). It mustn’t be over 39 degrees.
Small puppies often itch. It doesn’t bother them. It will vanish with age.
It is normal. Temperature in the flat/house influences him, as well as emotions after moving to a new place. You should wait a couple of days.
No, he has no flea. The reasons of scratching may be: 1-shedding 2-he is alive (we also scratch sometimes).
He must nobody anything. All develop differently. If you have doubts – consult the breeder.
The way the puppy sits does not indicate to dysplasia.
The puppy should get all necessary vitamins and elements to grow properly. It’s possible if you give him quality balanced food.
More info about food (soon).
From the very first moment in your house.