I think maybe some of the thought patterns that are present when you are in psychosis are coming up. That doesn't mean you're in psychosis though. You have good insight. You were able to quickly recognize it as a delusion. Maybe take the opportunity to explore what the feelings of being watched are all about for you. What do they represent? Why do they cause you so much fear?

I'm not discounting what WC offered. That was sage advice based on your patterns. I'm only suggesting that maybe you can work on these patterns a bit when you're in a state that allows them to come through to your world on a smaller scale than full blown psychosis.