Translation:I like my room, especially my bed.
Maybe it's a cultural thing, maybe it depends on the living conditions? I'd never call my room "sypialnia" (bedroom), although my bed is there and I sleep there. But my desk and my computer are also there, so to me it's simply "mój pokój".
I'd only call "sypialnia" a room in which one spends almost no time during the day and goes there mostly to sleep.