I'm sure your sweetie looks just fine. I've never seen a yorkie that doesn't look anything BUT cute!
I'm sure you are disappointed. I would be to. I lucked out and found a wonderful groomer and she comes to my house too!
I've learned to take pictures along to show the groomer when I want to make any changes in the cuts I have on my dogs. It does help some groomers and then others, well....
It sounds as if your Yorkie has a very silky coat. If that's so, they can often be very slow growers. But it will grow back.