Timeout

Ryan and I just got home from running some errands and when we walked inside he threw his shoes against the wall. I asked him to pick them up and put them away nicely. Instead, he went up to his room and shut the door. 

I had to get lunch ready so I welcomed the silence and let him stay upstairs. A few minutes later he came down, marched right up to me and said "I go timeout. I not happy with you. Put my shoes away. I sorry". Then he hugged me. 

On one hand I'm kind of proud that he knew he did something wrong so he went to his room to "think about it" and then when the time was up, acknowledged his behavior and apologized. 

On the other hand, I'm a little concerned that maybe I'm putting him in timeout too often. Is it normal for a two and a half year old to perfect the timeout routine and be able to execute it with no parental assistance??