That's really poor behavior on that person's part. Just understand that the behavior you experienced speaks to that person not growing up and thinking straight. Nothing on you, it's entirely on their end. They are uneducated about this and may even have personal issues themselves. For me, whenever someone acts in that manner in public, there are certain scenarios where it actually boosts my confidence. Because I can mention that it's a speech impediment and defend myself. I know I am in the right, they are in the wrong, and that I more than likely know far more about stuttering than they do. Either they back off or they get educated in front of a group of people. Either way I'm winning that confrontation.