I have a 2000 GOLF GTI 1.8T with an alarm system that seemed to have broke over night.

I drove my car last night and it was fine, but woke up this morning to find out that the remote key would not work. Not only that, the alarm is armed on the car at all times... even when running, and unlocked. It goes off when the passenger door is opened, the trunk is opened, or when the car starts. It goes off for about 30 seconds then stops. I tried replacing on the battery on the key too and it still doesnt work. So i think it's something to do with the wiring? This literally happened over night. The alarm is armed even if the car is unlocked and or running. I can't start the car with out it going off. Any suggestions?