Yan had a lot of stress to deal with. Especially with Shen Wulong constantly being out without anyone else realizing.

He didn't even notice he was gone at first, till he called him about fifty times and found out he was getting drinks with the people they considered their enemies...

The 'connector' really was going to be the death of him.

You find him sat by the table, with his head in his hands and his eyes closed, clearly agitated st something, and so you decide to go speak to him to see what's up.