My dogs puppy is very unwell...

Congratulations on the enlargement of the canine family :-)

The young pup may be too weak or he may have had a tougher journey down the birth canal in comparison with his brothers. It is strange the mother doesn't take better care of him, but she might feel his chances are low and therefore prefers not to get attached.

The first thing to do is take him to a vet. You might have to give him some milk substitute because he's too weak to suckle right now, and clearly too weak to fight his brothers for his mother's nipples.

Good luck 

it   well get better

There are so many things that could be going on with your puppy.  I would definitely take the puppy to a vet, just to get him/her checked out.  Hopefully, there's nothing serious going on, but it's worth getting him/her looked at.  It is possible that the puppy could just be developing slower.  It's impossible to know though without a doctor.  I hope your puppy is OK.  Good luck.

-Gabe 

I think u should take it to the vet and they well tell u whats wrong with him... And mabe they well have something for the puppy

Congratulations on the additions to your family!  The puppy that is not thriving may have neurological issues that only a vet can diagnose.  While you can support its basic functions, it sounds like it may have some special needs that your vet should address.  I am particularly concerned about the "bulbous head" and the circling behavior, as that can point to some serious defects that need immediate attention if it is to recover. 

Sending you cyber hugs and good wishes for a good outcome for this! 

I don'y know but I have a Lab pup 3 1/2 weeks old who can't walk and his 6 sibling are getting around very well...his legs don't work right and his rib cage is flat..I am going to the vet with him friday I will let you know what happens.

try to take for a walk or go to the vet and get it check out

Maby it sad or worried that happen to most puppies and hope your puppies ok