Your episode does have an implicit conflict, though, and it's precisely the one you're saying: you have set up an implicit conflict between your auditory perception and expectation.
(Actually, there's another implicit conflict in there which I would argue is perhaps even more important: why did you wake up so early, and why did you choose to go down the stairs instead of back to sleep?)
(Actually, there's another implicit conflict in there which I would argue is perhaps even more important: why did you wake up so early, and why did you choose to go down the stairs instead of back to sleep?)