As much fun as it may seem at the time, NO ONE should be exercised to the point of exhaustion. All reserves are gone, leaving the pup (or human) at an extreme disadvantage. If she were a human baby, it would be called abuse.
Playing until she's tired and you know she's going to sleep well is ONE thing; playing with her until exhaustion sets in and her system goes haywire is quite another. Just remind your friends that she's a baby and needs her rest ...
. If she's like most dogs, she wants to please you and will try to do so until she drops. But it's not good for her, as you've seen.