If you are enjoying your music and playing well then just carry right on doing so. I do not see why your appearance, or somebody else's opinion of it has any relevance at all. How would your pupil possibly know how you felt anyway ? You might have just had a bout of wind and gone pale from standing up too quickly for all she knew.
At one of these concerts she felt that I was so intensely in the music that I was completely "gone away" as she expressed it, being in different world.