If you refer back to the "Typical Day" section, you'll notice the word "vomit" in there. We were just kidding—sort of—but as you well know, people who are nervous do all sorts of things: vomit, throw things, lash out, run away, etc. And if the folks who are your patients know that something is probably expected of them, chances are, they'll be nervous about it. So they may act out in one of the ways we mentioned previously.
But it terms of careers that truly present physical danger to you, music therapists are toward the bottom of a list that includes—at the top—Border Patrol Agents, fire fighters, and oil rig workers. Then again, being a music therapist may present more danger than, say, a florist.