Should the doctor have used gloves to do the ultrasound during my amnio?

Yes: I would argue that any medical procedure done by a physician these days should be done with gloves. Actually i can emphatically state that any procedure involving a needle introduced into the body, should be done with the examiner wearing gloves and for a surgical procedure, sterile gloves. Yep, i don't think anyone will argue with that statement. Nonsterile gloves are ok for simple blood draws.