Odd Psychic Imprint

I just recalled an odd little experience I had several years ago while I was in high school. I was in 9th or 10th grade, and had to visit a dentist for an extraction. Now, I was -- and still am -- extremely terrified of dentists bearing needles. It's absolutely nerve-wreaking to the point of tears.

Anyway, that day my mother had to literally prod me into the dentist chair. In an effort to calm myself down, I clasped my hands together tightly (visualize an arm-wrestling grip) while the novacaine shot was being administered. The extraction itself was routine, and there were no complications.

Afterwards, as my mother was taking me home, I noticed that the top part of my left hand had a visible imprint of my right fingers. My skin was a normal color, but there was a faint outline that was slightly darker from where I had grasped my hand nearly an hour earlier. It actually appeared almost airbrushed. This imprint stayed there for over two months, before it completely faded away.

My guess is that the imprint was a result of a stress or fear-induced psychic or electrical charge. Has anyone ever heard of anything similar to this before?