It sounds like you had a great live-fire exercise from which you will be better prepared mentally, the next time an incident occurs.

Give equal time and thought to what you did right (fire stairs, communications,getting a mask, direction of movement), as well as what didn't work well (forgetting PSK).

Congratulations! In the event of an actual terrorist attack, you'd probably have still been able to post your bulletin, because you're ALIVE!!!!!