1999 camaro factory alarm

1999 camaro factory alarm system.  has worked fine since I bought the car, Last night it decides to go haywire. I used to have to hit the lock button twice to arm it. now as soon as the car is locked and the doors are shut, the alarm goes off. it just arms itself and proceeds to go off. so for now I cant lock my car. doesnt matter if I lock it with the key fob or the power door lock button. if anyone can help me here I'd be appreciative. I'm going back out to the car to try to disconnect the shock sensor(bad?) and see what happens.

Jacob

Thanks for the info auex but I think I just figured it out, tell me what you think. I just disconnected the shock sensor and everything is back to normal, so I assume it was sending a "I'm getting messed with" signal back. Now, can I safely assume that replacement of this part is all I need to do? what would cause the sensor to go bad in the wee hours of the morning? the light on the sensor was blinking at a high frequency, I'm not familiar with what this is indicating. again any help is appreciated, thanks

Jacob