Heard an ultrasound (heart echo) through my neck - what's going on?

Factual Questions
1

I had to get an echocardiogram, an ultrasound imaging of the heart. Whenever the device was pressed into my chest and on, I could very clearly hear a high pitched squeel - which I localized as coming from the back of my neck, in my spine.

It was totally clear - no ambiguity, no faint sound. If the device was touching my chest but not pressed into it, I wouldn’t hear a sound, but as soon as it was pressed hard I would hear it. Which I suspect was some sort of bone conduction all the way up to my ear, and my ear somehow localizing it incorrectly as coming from my spine.

So I asked the technician if that was normal, and she said that she’d never heard of anything like that happening.

So now I’m wondering what happened? If it is some sort of bone conduction, how does it slow down from an ultrasonic vibration to something my ear could interpret, or is the same frequency somehow audible if it comes down the bone instead of through the air?

2

Happened to me, too, when I was having an ultrasound for gallstones (and not, years later, when I was having one for a relapse). Seemed to be my skull, in my case.

The doctor said some people could hear it. His guess, like yours, was that it was the bones vibrating (slower than the sound waves because they’re embedded in mushy goo…i.e. me).