His room was cleaned two days earlier....

OCD DOES NOT MEAN PERFECTLY NEAT!

I used to think that people with OCD were always terribly neat -- like Felix in "The Odd Couple."  Now some children and teens with OCD may be very finicky/rigid in how their belongings are kept or arranged, but not all are. The child whose room this is had Tourette's Syndrome, Attention Deficit Hyperactivity Disorder, and OCD. Shall I bother to point out that he also had a lot of Executive Dysfunction, reflected in his inability to organize well?  

Other signs of OCD that appear in the photo include the somewhat destroyed corkboard bulletin board above the bed. Once the corkboard started to crumble, he "had to" keep picking at it to "even it up." What started as a a bit of cork missing grew to the empty area you see above.