No. Read your owners manual. The page I posted is from the US manual.One of the reasons the LED keeps flashing for a long time (I think this is what you are experiencing) is when the second key is left inside the car.
The beep will most likely be an audible warning as the system has detected a fob inside the cabin was used to lock the car and the audible warning is to tell you that the arming of the alarm is in progress. If you were to open the door to exit without turning the alarm off you will trigger the alarm and get flashing indicators and horn as if someone was attempting to break into the car. If you lock the car from outside with the fob the internal beep may not be present. My previous Pajero/Montero exhibited the beeping behaviour though it had a premium OEM alarm with ultrasonic sensors inside the cabin.I did a quick check and could also hear an intermittent beep along with the continuous flashing.