Alarm keeps going off!!

[bEchev25]

Left my car in the mechanic a few days ago and when I picked it up it need a boost to startup. Mechanic told me I needed a new battery.

Left it home parked and it wouldn't start at all. Something is completely trained, to the point the car fob doesn't work, so I use the key to open and close.

I closed it earlier but the alarm keeps going off on an interval. I tried opening and closing again, nothing. If the battery is dead, why is this happening? How do I stop it

I don't want to be a menace to my neighborhood