Cause you're not disarming your alarm, it's probably aftermarket.. Yeah you need a new remote, the engine is disabled unless you disarm the alarm...
You need to find out if you're alarm is aftermarket or stock (came with the car). An easy way to know, if you could still remember the remote, if it said "Cadillac" or was just blank it was prob stock, you could take it to the dealer. If it said something else (viper clarion, black widow, etc.) then it's aftermarket. If you can't remember, look under the steering wheel. If you can't find it, look for a siren and follow the wires...
