I have the same problem. I get a weird spasm/tic when I get a block and then I see the other person notice or they say something and it throws me off and snowballs the whole thing. I think the fear of it happening can be just as triggering as having it happen so a large part of overcoming the issue is convincing myself (sometimes successfully) that it doesn’t matter if I block or have a weird tic which paradoxically stops it from happening.