What should I do if everyone knows my most shameful thing?

What has happened, don't think too much. Because, everyone has their own career and their own focus, maybe they don't care too much about what you call shameful things. Sometimes, it is your own unnaturalness that causes them to notice what they almost forgot, which is self-defeating.

Of course, some people will say that they have noticed it, and even laugh at you because of it. Don't care too much at this time. Regret for what has happened is a bit putting the cart before the horse. You don't have to do this at all. In this case, you should be strong, get through the initial stage, don't be angered by the ridicule of your colleagues, and don't force yourself to explain. You can even laugh at yourself without words. Let time dilute everything. After all, the more you fight back, the more excited they are, and the more likely it is to be remembered. Reluctant defense and counterattack are pale and powerless.