Here's some tips for lighting because I happen to be pretty good at that..
Most people have the idea that for a game to be scary or horror themed, it has to be really dark. Contrary to popular belief, that's not necessarily true; it helps sometimes but if the whole game is dark then it's just annoying.
The trick to making it creepy is to have plenty of places where things are well lit, it provides contrast. If the whole level is dark, well it just looks like a dark level. If you have a flashlight that's one thing but even then. But if you have lots of lights, players will feel uneasy when they suddenly have to go into a dark place. A general rule of would be that if a room doesn't need to be dark then don't make it dark.
You seem to have lights in all the right places for the most part so what I'll suggest is to make all your lights much brighter. The way it is right now it's sort of hard to tell if they're lights or just ambient lighting. Increase the brightness and that makes shadows more visible too. You want it so that where there are lights, all the details in the environment are visible (textures, models, etc.).
For example in screenshot #10, if you make that light way brighter it'll feel like a safe place because now you can see well. You let your guard down slightly making it the perfect time to make a zombie pop out from the darkness from one of the corners. Psychology plays a big role in the use of lighting, use it to your advantage.