11month old puppy having "panic attacks"?

[evanora]

Eko is my 11month old puppy who I adopted at 8weeks of age. She was written down as a bichon/poodle with possibly havanese thrown in. As she grew, every comment I received (and still do) from people was "Wow she's long! Does she have dachshund in her?" so it's possible she may have some of that mixed in there as well.

Since she was a young pup she was introduced to tons of different races of people people, plus children, the elderly, men, women - you name it! She was taken to obedience/agility classes set up for beginners, I'm a dog walker so once she had all her shots she has accompanied me on all of my outings and met every type of dog (big, small, neutered/spayed and unfixed). She has traveled in cars, buses and on the subway, LOVES swimming/water and is a nutbar.

Then, things kind of went "weird" with her due to an incident with the park bully dog (who is never on leash and has attacked several dogs because she runs out of no where and lashes out and the owners do nothing - mix between a lab/shepherd/border collie). The female dog attacked her/chased her down right beside me (three times) and of course, the other dog was off leash, Eko was on and all Eko did was scream/howl and try to hide in my legs until I chased the other dog off. Since then she barks/wails at new midsized to larger dogs (even if they are on or off leash) and it doesn't matter if she's on or off leash. It's very hard to talk her down (which is me trying to use her clicker training, positive reinforcement training or even just redirecting her) once she gets into this state of "panic", and also it's quite embarrassing as people usually call me the "dog whisperer" of the park because all the dogs I walk in the neighbourhood behave the best for me - except my own, now (apparently).

People have suggested that she no longer has the confidence she had when she was younger but having tried so many forms of training with her (and she's super bright so she catches on quickly) and none of it seems to soothe her in these times of panic, I'm at a loss. It's heartbreaking to see because she enjoys other dogs so much and all the dogs she has known regularly from her young puppy days (dogs up to 115lbs!) she still loves to death and will romp around and play with, but new dogs... it's like her brain shuts down and she can't just accept that it's okay to have confidence and be carefree - all she does is wail/bark and completely freak out. I can't take her to off leash parks anymore because her tail is down and she just stays beside me, when once she ran around and played.

She's super attached to me and is great when people come to our house, but also on the street she will not go up to people or kids anymore. I'm willing to give anything a go!

Her "brother", my 11.5year old helps her at times as if he goes up to a dog she sees it's "okay/safe" and will sometimes follow. But I'd like her to have that ability all her own and not bark (it's a fear based bark) and have fun with new midsized/larger dogs like she used to.

Any advice is greatly appreciated! (apologies for the length)