William was a biter as a young pup and a hard mouther to boot. We found that he got over excited if we played games with him which set off his biting and attacking fits.
Time out in the pen, and ignoring him seemed to work best for us, but he has grown out of it and is now the most gentle mouthed of spaniels.
This phase does seem like it goes on forever, with William it was several months; at times we would have been grateful for other family dogs to divert his attentions and teach him some manners!
Pups do vary in their attitudes, but at ten weeks he really is still finding his place. It is easy to think at times this pup hates me, but no its just doing what pups do, give him time and try not to re-act when he becomes wearisome, easier said than done, as I so clearly remember.