Anxiety.

Yang Dao sat under the tree gazing at the stars, the gentle breeze caressed his long hair. The boy was lost in thoughts of the words spoken by Xiao Jin. He did not wish for his family to enter a war. Although the Yang family has been hiding their true strength because they did not wish to have anything to do with the secular struggles. 

If a war broke out, the family will have casualties even if they were not too many. As he sat drowned in thoughts the night faded away. In the morning Yue Ling appeared next to him. She asked in a low voice, "What have you been thinking about?" 

Yang Dao replied, "The threat issued by Xiao Jin. For some odd reason, it has agitated me. I do not know why, but I cannot calm down." 

Yue Ling raised her eyebrow and asked, "Could it be that you are overthinking the fact?"