Ok so I just "finished" Amnesia, but I barely had half an hour of gameplay?! I started in a room with an oil lamp, came to a room with one monster, climbed up a ladder, crawled through a small corridor and came out above a library. Found some stuff in said library and snuck into a hidden door behind a bookshelf. Then I ran through some rooms flooded with water and avoided some monsters again, arrived in a room where I was almost killed Star Wars garbage compactor style but survived in the end and could leave up a starwell.
Fade to black, credits, The End. What am I missing here?