I understand this. I've had this happen, but I try to really laugh it off the older I get so people don't see my anger behind the stutter. I do get angry at myself, but it always goes down better if you can laugh it off, which I know is hard. I think I have the opposite issue - that I feel people think I'm boring because I'm trying to talk more slowly. If I can speak at a slower pace I don't stutter as much, but I do worry people perceive that as me being bored or boring in conversation.