When I was dating my husband he went into a block and I got freaked out inside. I went home and told my brother about it and later confessed to my husband what I said about his funny faces. He did look a bit annoyed but you have to realize it’s hard when you’re not wearing those persons shoes. I’d get thicker skin. Let them know you were hurt by their mockery and if it happens again, write them off. But first time…. People don’t know unless they are walking in your shoes so Id try to give them a pass the first time. Same thing with being a minority. I’m sure you’ve innocently mocked some other race’s stereotype. It just means you need some training to appreciate other cultures… same with having a stutter but I got you how some people can be insensitive like that.