Driver door lock won't lock unless manually pressed
 

The other day I went to get in my car and I opened the drivers side door but the alarm went off. Figured out that sometime very recently something happened to the drivers side door lock such that locking via the key fob or the arm rest button won't lock the door. I've looked up how to remove the panel because I was planning on trying to fix it myself but I wanted to see if anyone else has had a similar problem.

I'd check for a blown fuse or a wiring/connector problem. Possibly the connector near the door hinge. Could be a bad solenoid. FSM (link in my sig) has wiring diagrams, fuse locations, &c. A cheap VOM will come in very handy.

Edit: It might be worth a shot to disconnect the battery, step on the brake pedal for a few seconds, then reconnect the battery. This will reset the computers that control the car. You will need to do a window reset and reprogram the radio presets afterwards. And the car may run rough for a while until the ECM relearns the engine. I don't have high hopes that it will fix your problem, but it's a lot easier than pulling door panels and wringing out wiring. ;)

I know their are some options with the fob, setting up how the door locks and sounds and lights

Check your door pin switch. Test for continuity. If there's no continuity, clean and lubricate contacts or replace switch. Start with this first, check connector and wiring next.

I'll do that, don't want to take the panel off only to find out it wasn't something not behind it. I actually just replaced the battery, I'm fairly sure it was the original battery ('09, bought used in '13 with 30k, 42k miles now).

The only one I know of is that you can make the lock silent or make noise by holding the lock and unlock button. Since the button on the arm rest won't lock or unlock the car I don't think it's something that would have been done on the fob.

I'll do that too, wouldn't want to remove the door panel and have it be something not behind it.

Disconnecting the battery and pressing the brake didn't help. Which fuse would I be looking for? It seems odd that the passenger side will still lock/unlock and the drivers won't if the issue were a fuse. Door pin switch (if I was looking at the right part) seems to be working, with the door open if I press it the window goes back up.

Where should I look as far as connectors/wiring? I'm not a huge car guy but I am a pretty good DIY kind of person. I'm getting the feeling that the problem is behind the panel, and since I'm hoping to upgrade the stereo next year I'm actually not too worried about taking the door panel off.

Well, that rules out the door switch and the connector/wiring. Now, it could be the door lock actuator itself.

Thought I had included that the passenger side was still working in my original post but I didn't. I'll have to try and take a look behind the panel in a few days when I have the time.

Some plastic/nylon pry tools will help remove panel while minimizing scratching. You can find them at most auto parts stores for a few bucks.

Door randomly decided it was going to start (kind of) working this morning. For the most part the arm rest switch was able to lock and unlock, didn't test with the keyfob.