puppy play group

I just got back from my 3rd puppy play group. Mom says there were all kinds of puppies like a bulldog, a spinone italiano, a puggle, a couple labradors, and some mixed breeds. But all I cared about was this little, white maltese named Brooklyn. I kept trying to play with her, but for some reason she would tease me, and act like she wanted to play, but then get yippy when I would actually try to play with her. I don't get it. Girl puppies confuse me.....