I'm fairly certain that icon has been a part of the software since the last update done earlier this year. It's just that it will only show up when a member deletes their own post -- which very few members do. That's probably why you haven't seen it before now. (The community support team doesn't delete posts -- we move them to another admin-only forum in case there's a problem or change of heart regarding the post.)

One icon shouldn't cause anyone anxiety. The forum has a lot of features and functionality, and I wouldn't expect any single member to know how it all works. Nor would I expect any member to believe they've caused something to change in their display if they haven't done anything to change it.

Sorry this upset you. But please know that you aren't expected to know what every single icon means, and that's okay. That's what this forum is for, but it shouldn't cause you anxiety if it happens again in the future.