What does it mean if you’re talking to a guy you’re sort of crushing on? And he gets a little upset that you texted him back late and then you explain the situation and then he understands why and then afterwards asks if I have school and to text him later when I’m done.
why is that?
That is a very confused person that seems to place a very high importance on instantaneous replies on social media and does not have the patience to wait a while for a reply.
I also suspect that he is jealous and thinks that you are communicating with other people, not just girls but mainly boys. That would put him in a "potentially toxic people" category that wants to try to be in control of what you do and when you do it.
He wants to make sure that you are not talking to others and that is why he asks you or better, orders you to call him right away when you are back from school.