Concerned about

He doesn't seem too concerned about getting back to school, or much else for that matter.

(Context is that a boy hasn't been to school for a long period because of some psychological problems and his mom wants him back at school, but he doesn't seem to care that he's not in school or anything else.)

Does "concerned" here mean that "he" doesn't care about being away from school and is not hurried to get back? Because I don't want it to mean that he doesn't seem worried to go back to school, because he's not going back there at this point.

If not, could it be rephrased? Or can I just not use "concerned"?