
Hi! This must be the most common problem for all puppy owners! All puppies use their mouths to learn about the world (after all, they haven't got hands to use!), but it takes them quite a long time before they learn what silly softies we humans are, and how gentle they have to be with us.
As you've discovered, a 'yelp' noise, especially if a puppy has been encouraged to play with squeaky toys, can be very exciting, and wind the puppy up even more. Children, too, have naturally high-pitched voices which also excites the puppy. There are several methods which work, and you'll find out about them on
this link (click on the underlined blue words). Also I think your whole family would find a copy of "The Perfect Puppy" by Gwen Bailey very helpful - it's full of lots of useful tips on puppy-rearing.
Basically, the calmer the puppy's surroundings, the calmer she'll be. It's up to the clever humans to notice when she's getting over-excited and call 'time out' to the game till everyone calms down! Good luck with her!