Ditto...
Mindy is the same way, she hates being sniffed. It's ok that she sniffs butts & as long as she wants, but,
Nobody is allowed to sniff the "Fun Police", it's against the law & you don't want the wrath of Mindy's teeth
clamping on your nose!
I've got one of those too! Princess LOVES Meet & Greets because she LOVES people, but she doesn't like other dogs (especially strange dogs) to get in her face or sniff her butt. She growls a warning and if they don't back off she will snap at them. I always walk her away when exuberant dogs approach her head on and explain to the owner that she just doesn't like other dogs rushing up in her face. She's also just fine with rushing up in another dog's face or sniffing them mercilessly, but don't even think about doing it to her, 'cause that's a whole different story!
Kennelmom makes an excellent point about looking at the situation from the dog's point of view. And just because she was uncomfortable on this initial outing, it doesn't mean she'll never be a good M & G dog or will always be "antisocial". Watch/listen to her cues and give her some time, space, and exposure.