He was tired

Deku, the poor boy was overworking himself just for those civilians. And how did they thank him? "DON'T LET HIM BACK TO UA!!" and all those bitching words. They should've be grateful..were they? No. They let him in pain for them and then still bitch about feeling sCaReD.

Well. Afters Ochako's speech they finally let him in. He was forced to take care of himself.

"Thank you..for helping me out. And..I'm also sorry for leaving like that." Deku said sadly.