Lump in puppy cheek bone

Puppy is 10 weeks old. Picked him up last week when he was 9 weeks. One of this litter mates was a bully to him and this resulted in her biting him just below his eye a few days before he was picked up. The breeder had been cleaning it and the swelling went down by the time he was picked up. Now, a week later, the area that was injured as swelled/grew again? Does anyone have any idea what this could be? Apart from him being a bit quiet he seems fine. Today it now has an indentation above it?? It is a hard lump

Hello!  It's boring, but I have to write it:  we always advise asking for first hand veterinary information before buying a pup with a known illness.  In this case, if this was indeed a bite wound, then bacteria from the (biter) pup's mouth wound have been injected deep into the tissues by the action of the bite.  They could sit there for a day or two but of course the fascial tissues are warm, with a good supply of protein, so any bacteria would multiply fast causing an infection,  access or, more superficially, cellulitis.  Bathing abscesses almost never sorts them out because the infection is well below the surface.   Whatever this is, it is a great idea to show it to a vet asap.  Mention how young the pup is and that it's a possible bite wound when you call.  You may want to consider the emergency vets for triage. Best of luck to all of you and please do let us know how you get on.

Oh dear the computer has spell check ed my answer.  With apologies:  I meant facial tissues (ie the muscle of the face where the bacteria might be sitting after a bite wound).   When bacteria multiply fast causing lumps, the lumps are abscesses (I wrote access).   Sorry!