Yes, that's what would have happened.
When you disarm the panel via a code, the Omni kills the power to all the smoke detectors for a second to reset them... then powers them back on.
If the smoke alarm trips again, if you have verify smoke alarms set in the configuration, it will even kill the power again to re-reset one more time.
If the smoke is still there, the detector will trip again, and the panel will go off again, and you will get a notification again.