Hi I have a full blooded female fixed Shihtzu that is 15 months old and I got a full blooded female Pomeranian that is 8 weeks old. When I put them in the floor together all they do is play fight. They constantly bite on each other, roll over each other, chase each other. So far the Shihtzu has only made the pomeranian yelp about 3 Times and the pomeranian hasn't made the Shih Tzu yelp at all yet. My question is this behavior normal and how long will take for them to calm down. I tend to separate them after about 10 minutes because I am afraid of the pomeranian getting to exahushted. Any insight on this will be greatly appreciated..oh I have not seen any sign of real aggression or anger out of ether dog although the pomeranian will growl occasionally.