Really big boy bed

Will has been in a toddler bed since he turned 2 but this past weekend we finally bit the bullet and got him a twin bed/mattress. He slept in it last night and loves it. He seems so small in the expanse of the bed. I am sure that will change in a few short years and before I know it he will take up the whole thing ): The bed itself is so much bigger than the toddler bed that we had to reaarange his room. Now it seems like his whole room is the bed!!