Whats wrong with my puppy?

I just got a puppy that is about 5 weeks old and when i got him he was fine.Ii have only had him for 2 days and yesterday i had notice that around his nose and in between his eyes started to swell. It looks like there was puss coming out of a small area near his tear duct and in the in between his eyes was a spot too.I tried to wipe the puss off with a warm wet wash rag and he started whining so i could not get all of it, but it was green and really thick. Please help me because i don't know what is wrong with him. What do i need to do and what is it?