Nope, not as far a I can see.
I have worked closely with people senior to me all my life.
I observed them all very closely and learned a huge amount.
If you're a good, honest worker, you should have no underlying problem.
However, "real grounds" aside, the fact that you feel intimidated is itself a ground.
Some people can impress merely by their presence and/or intelligence, and a shy person can feel intimidated.
When strength of personality is augmented by their very real power over your career and finances it can be overwhelming.
Talk to your HR manager or Line manager, but if its a small company its a difficult call, particularly when the "problem" is the boss.
Sometimes chance seating arrangements can be career-makers or career-breakers, depending on how well things go.
I might suggest a different desk arrangement - right angles, not facing - and I would not refer to it being the boss behind you.
Definitely don't ask to be moved away fro the boss - think of the message that sends - and try to improve your professional relationship.
ONQ.
All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and business professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.