Yikes, I feel your fear though. I live in a big city, and where I used to live had a lot of problems. (granted, where I live now isn't that much better, but there are always a ton of cops out.) Someone tried to break into my apartment while I was asleep! My landlord got me this big pole that can be adjusted. It sat under the door knob and the leg extended to the floor at an angle. It basically prevented the door from being opened without serious force. If you can find one, I would recommend getting one. After than night, I slept with a hammer next to my bed too, just in case.