Sometimes, Pam gets panic attacks, it's no big deal.
Sometimes, Pam gets panic attacks at work, then it's a bit more of an issue.

Set in season 3. No specific episode, but Pam is with Roy and Jim with Karen. 

'The main source of her distress laid on the table, almost shining under the lights. Pam knew it would be hard to break with it but had no idea how much.'

Set during and after 'Benihana Christmas.'

Jim and Pam go to Jim’s house for the night after what happened in the lobby, both almost ready to crack.

Takes place after Night Out, and is canon compliant. 

The CIA needs receptionists, too. A short, silly story where Pam ends up a clandestine operative. Post Negotiations. 

'He thought that one day when things were finally right between them, he would tell her about this evening, and the painting, and the sun in her hair. But this day hadn’t come yet.' 

Set before the seasons (and in AU).