Yup, you were right. It turned out that the lock on the front passenger door has gone bad. The reason it was beeping at me a second or so time was that the car realized that the door didn't lock/unlock the first time so it gave it a second try. For a couple weeks the second try worked, but now that lock only functions manually. Honestly its not too big of a problem for me, but my girlfriend is getting tired of me reminding her to lock her door when she gets out. I guess its time for me to lookup the posts for how to replace an actuator. I can't say that I am particularly thrilled, but if this is the only thing wrong on a 2001 car w/ 115k then i guess thats not too bad.