car alarm will not turn off

i left my lights on. came to the car the next day and realized it was the battery was not working. i then instantly bought a jumperbox but once i hooked it up my alarm turned on. everytime i open the car door now the alarm turns on and that has never happened. the alarm is stopping my car engine from starting. how do I turn off my alarm sot that I can jump my car? please help. i have done technics that i read online and none of them work.