Don’t you sometimes just know they’re watching? Observing personally you, for purposes arcane and unknowable, maybe even nonexistent? Biding their time, recording your every move, checking on you in a detached, efficient & passionless manner? Caring, yet not caring, almost benevolent in the absence of any tangible malice?
Of course it’s nothing like that. It’s just the NSA and their myriad local counterparts. And your own paranoia.