>> Currently the two pups are very agressive with each other and are very noisy, this also concerns me as at home my pup is very quiet and well behaved? <<
This is because when he is with the other puppy he can play and enjoy himself when he is home he is propably fed up, it is not normal for a 14 week old puppy to be very quiet and well behaved, he should be playing his socks off.
I keep males together, but never of the same age, have to say I have no problems at all with my intact males, did have some trouble with a castrated one though. It would probably be better if the 2 pups were left together all the time and then they would settle into a more normal behaviour of some play, some sleep and some eating, as it is I don't supose he understands what is going on, and would not think of living with you as being home.