Sounds like she just wasn't ready for an energetic puppy to be all up in her face... and she let the puppy know, in no uncertain terms... to back off. I would have walked her away (like you did)... then had her sit and observe the puppy from a distance for a while before leaving for good. Just so you could leave with her observing the puppy in a positive light. That way the next greeting may go better (or not...).
Definitely plan more for your next meet & greet with a puppy. Maybe seek some other puppies out if you can for some practice.
There is a "coming of age" shift around her age, sometimes (we didn't see one in Denna) - so you might need to step up the socialization plan for a few months to help her through it. Keep up with confidence building exercises, visiting new places, greeting new people (practice the formal "sit & wait" for greetings), etc. Make sure you end all interactions on a positive note - even if it's just sitting from afar to observe the object that might have triggered a bad response. Let her know that walking away is always an option, and snapping is not recommended, and that YOU will be there to support, protect and help her through it all.
If you do bring a puppy home to live with her, make sure she always has a safe, quiet place to retreat to that the puppy is not allowed to go. Give her lots of attention and one-on-one time, so the puppy is just a new fixture in the house to ignore, until she feels comfortable enough to engage with the puppy herself. That will take controlling the puppy, too, of course, which might prove more of a challenge.