I suppose the question is how do you display your nervousness ? Loudly, internalise, resent, appease etc. AND, more importantly why are you nervous?
People who abuse their power trigger me due to my past trauma. I go on the offensive, slicing them down to a size I think is appropriate. Obviously this isn't ok behaviour from me… who says I'm right and what's the 'right size'… so I try and look at things from their perspective and ask myself why I'm feeling like this and is that feeling justified.
You can't stop your unconscious immediate reaction / feeling, but once you've noticed it, you can then consider your options.
That might not have made sense. Sorry.