Who defines what a warning sign is?
The clinical team, in writing, in the protocol for each kind of care. The system doesn't invent criteria: it recognizes what the clinic wrote and routes it.
What happens when a patient reports a sign?
The report goes to the team's queue ahead of everything else, with the reason and the time. The patient sees that the team was called and has the clinic's emergency contact at hand.
Why record everything?
To know later how long it took between the report and someone on the team acting, and so whoever takes over the shift sees what happened without asking anyone.