When you live in a tiny apartment, you get used to it and you don't notice how cramped and restricted you are when you don't have much space to move in.
When you move into a bigger house, or go into a huge room, you get this feeling of expansion and freedom.
I think my head may have been like that. It was all small and cramped but I didn't notice. Now all of a sudden, I feel like it's a big, open room.
And I wonder how I didn't notice how small and cramped it was earlier.