I too am speechless. I hope that tech is fired on the spot. She has no business telling you that your going to die a long horrible death! WTH is wrong with her? And I am so sorry but I would trust my surgeon over a tech any day.
She's damn lucky it wasn't my girls she was yanking around and getting mad at or she'd find herself getting a headogram!
If they are affiliated with any hospital, I'd also go ahead and call the head of that hospital and let them know how you were treated.