Why does my puppy pee every time I do?

I know this is weird because I have searched and searched and have not found any similar experience on the internet. Whenever I go to the washroom to urinate, my puppy inevitably will do the same somewhere in my apartment. It isn't as though he has to go really bad either, because it is usually a small pee. Is he marking his territory? Does he feel threatened by me doing so? He is only 8 weeks old, just separated from his family, just getting used to his new surroundings. He is otherwise very well behaved.