Tony hadn't left the building. He was sitting where he was and was thinking, The genius didn't seem to be himself today. Though he still had moments where he was more like his normal self.
He really hated meetings and didn't care if he had walked out half way. 
People knew him for not really sticking around meetings anyways.

The receptionist looked at her "He is still here." 

Tony was closing his eyes. Even if his hangover was going away. He was moody for other reasons. He was waiting for Pepper so he could go home. He yawned still feeling tired. He looked around when he saw her.
"Pepper?" he asked noticing her.
He was a bit calmer now. Though what ever was causing him to snap was likely to cause him to again.