My period was seen by the whole class. What should I do?

Many people make mistakes in physiological phenomena, even adults do.

Not afraid of jokes,

Don't be ashamed, it means that you are an adult and you should be proud of it.

Pretend not to care, and what they say will be boring. The more you care about them, the more important it is. Pretend to be casual.

So we can't make them proud.