Ask your instructor if he gets air sick when being flown roughly by someone else?
You would be my choice as a potentially good pilot as your sensitivity to small accelerations is above average.
Our feel for those small accelerations/movements tell us what the aircraft (or other vehicle) is doing and what you are doing with it.
It will all change when you are doing the controlling and then the instructor may need the bag - that is unless he has a wide bristling moustache which signifies that he is from the old school when aircrew were not supposed to be sensitive to g and rapid variations of same.