98 olds weird beeping question......

Hi I got a 98 olds Cutlass v6 and I've had it for a few years. I recently had a driver's side caliper and both front brake pads replaced by a friend of my mom's. He dropped the car off to me right after doing the job. The thing is when I turned the car off I hear this very fast beeping when the driver side door is open. It does turn off when I shut the door. I had never heard this sound before in my years of owning the car. The beeping is not the car horn but like the sound when you insert the key just way faster. When the other doors are opened it does not make this beeping at all.

So when I went to leave a couple days later my battery was dead. I got a jump and ran it for about 40 min to charge the battery. About 7 hours later I went to leave and the battery was dead again. I do have a car alarm which is switched to off and I also have a remote car starter which I never use.

I fully suspect this beeping is the culprit and was wondering if any of you have encountered this problem before? Any help or suggestion would be very appreciated.

I feel dumb but I think my lights were on lol. I don't think I ever turned them on or off before because their auto.

Leaving lights on while removing the key will cause a fast beeping from the chime module. if the battery doesn't die anymore, then sure, there you go, just overlook auto lights