I don't know for sure,what you are experiencing but I can say I have done something similar when I thought something was odd and I worried someone wanted to break into my house. I got really scared and felt paranoid, and had to leave the house in a panic. It was never full blown paranoia in my case if that makes sense. However, I don't get full blown paranoia, and since you do I wonder if this is similar to anything you've experienced before? Are there any typical signs for you to be concerned, especially early signs to watch out for? Maybe asking your therapist their opinion would be helpful.