I've been planning a sitcom for the last year (if you count "planning" as occasionally pondering about broad ideas while bored) and have been writing it for the past month. In the beginning it all felt fresh, and modesty aside, rather funny. However the more I do the more predictable the jokes feel, the more obvious the set up. I'm not sure whether it's stopped being funny, or the jokes are too similar, or whether I'm just to close to it to see it anymore, but whatever the explanation, its driving me a little insane!
Do writers ever know whether what they are doing is funny?!