Look, crying happens. Sometimes it happens in situations we don't want it to. It can be frustrating, and annoying, and make you feel like you've let yourself down. But most people have been there and aren't going to write you off because you've shed a few tears. No one is in control 24/7; nor should they wish to be. Emotions are part of making you the excellent human being you are and if crying is part of that, so be it. If you can't face a meeting with your superior, you can always send an email instead, or try and get your tears out on someone you trust first. But if you do cry in front of someone important, remember it's unlikely to be the first time they've seen another person do this – they're not heartless, and they will give you some leeway. So get out of the situation, take a walk around the block and give yourself a pat on the back for attempting a difficult conversation in the first place. There's plenty more time for you to head back in and give it another go.