It is okay for your character to be irrational

It is okay for your character to seem stupid and make mistakes that are just as stupid

it is okay for your character to misunderstand

It is okay for your character to get angry, sad, or anything over something—even if it is simple.  

It is okay for a character to act out/lash out over something

It is okay for your character to be sensitive

It is perfectly fine because they are people. That is what people do.