Can you post a link? I am not sure what you are referring to.
ETA: I found the post you are talking about. It looks like you accidentally selected an icon when you were posting your reply. At the bottom of the screen where you type your response there is a set of icons you can select from. Probably you had an errant click and that is why that is there. Go in and Edit your post, then Go Advanced. Scroll down and you should be able to "unselect" that icon by selecting "no icon" so nothing shows there or you can select another one.