My son is alway late for school so I threw a baseball at him because he needed to wake up
That's no way to treat your son. Throwing things at someone is dangerous! Did he get hurt?
Of course he didn't. Don't get me wrong, I was just trying to scare him.
Throwing something hard like a baseball at a person when they aren't expecting it can really injure them and it is something that you shouldn't do. Instead of trying to scare your son awake, use an alarm or other gentle means to wake him up gradually that won't risk physically harming him.
It's fine, he's used to it now. I just want him to get up early.
I doubt "he's used to" getting hit in the noggin by a hardball while he's fast asleep! You could be prosecuted for child abuse if you seriously injured him. Try talking to him about getting on a regular sleep schedule.