A tired puppy is a good puppy. The day may have been the most fun for her since she left her litter. If the other dogs were young enough to enjoy play, they may have gone non stop. We frequently accept such guests plus when our daughter comes for the weekend, she brings her puppy. The puppies always behave very well anywhere we take them after playing together.
There is a possibility she was exposed to something. Keep an eye on her and maybe call the vet if she isn't back to normal tomorrow.
See the sticky starting at
http://www.askmehelpdesk.com/dogs/in...tml#post251802
for other info you may find helpful.