Security system?

Our '99 cougar's emergency lights were accidentally left on all night and drained the battery just after Thanksgiving. Next morning, jumped the battery, no problem. But ever since then, we have to jump through hoops with the security system to get the car to start. Don't know if it's connected to the battery drain or not. But today, the car won't start at all. However, the lights, radio, blinkers, everything else seems ok. Help! Is something easily fixed by a non-mechanic such as any of my family members (fuse, etc.), or is this something that I need to have the car towed to the dealership for them to fix? Save me money before Christmas if at all possible! What could it be? (By the way, I'm the mom of the cougar's driver.) Thanks for your help!

sounds like something might be up with your PATS system.

1st is it the factory alarm, 2nd does it have a remote start. i ask because i am a MECP Certified installer and we had a guy come in the shop with a 2002 escape witch has the same transponder system and the key he had world not start the car, his wife was playing with the remote start i did in it and she left the key in the cylinder when she started it. if that happens it will erase the code from the key.