Heh - I do find it's easy to get paranoid / overcritical about possible 'off' flavours in your own beer... give it a week, drink some commercial stuff then come back to yours and I bet it will taste fab ;-)So I did do a diacetyl rest but I think it tastes popcorny.
Not sure where I went wrong with the diacetyl test if so. Maybe heated it up too quickly?