As you can tell, it is very difficult to fully understand a situation without seeing it first hand. Perhaps everything will be ok and what you precieved to be major issue is really nothing other than puppy play.

I am not sure now if P.C. sounds like a big teddy bear or if he shows some dominance that needs addressed. The only way to address dominance is to have the owner be the dominant role in the pups life.

Perhaps you need to give this some time to work it's self out. If you notice any bloodshed then you have major issues. Play fighting can sometimes take on the appearance of being worse than it really is. If there is no blood shed then you need to let them work it out between themselves.

With Smokey being only 7 weeks old, it may be way to early to tell what the future holds. And I wouldn't get to upset over the potty thing yet. Just be consistent with him. He will catch on.