pkpk was crying last night and now her eyes are swelled up.  Tears are strange; you cry when you're happy and when you're sad.  This discussion of tears reveals a terrifying plot!
When you're happy you say "I'm 
happy. I'm really happy."
Cuando estás feliz dices "estoy feliz, estoy muy feliz".
Cuando estás feliz dices "estoy feliz, estoy muy feliz".
Quando você estivesse feliz,
 poderia dizer: Estou feliz, muito feliz.