Over-voltage protection

[Demon]

A little something I thought up in case a user doesn't use the proper power source (like use the Lab-X1 12V wall-adapter instead of the 5V model supplied with the unit).

This serves as both a POWER light, and a MAGIC-SMOKE-INCOMING light.

IF Zener receives under 5.6V THEN
  PNP transistor turns ON green light
ELSE
  NPN transistor turns ON red light
END-IF

Does it make sense? Am I forgetting something?

I've never touched a Zener before, and rarely have used a Transistor. So this also serves as a training exercise for me.

Robert