About 3 months ago, my German Shepherd started acting scared and timid when we go outside. We are always outdoors. Started in the back yard. She would either run to the gate as to say let's get out and if I didn't comply, she would come stand next to me, legs visibly trembling. If I don't move, she won't and she will only go back in the house.

She would still go out front and sit on the porch, but the same thing started out there. She drops her ball and stands at the front door, trembling and looking over her shoulder. She's clearly terrified of something...It comes and goes without any sort of pattern. I've tried audio testing. When it happens I measure frequency and decibels and there's never any deviation.

She's bad today. She senses something that I don't and I want to know what it is. She won't go outside.

Anyone else experiencing this?

I have two rescues, they both do this, but one is really bad, doesnt like to go for walks anymore.