[Always *]

I won't repeat what Cassado just said, so I'll skip to one of the other things I wanted to touch on. I think something else worth doing is finding a way to contact your friend - borrow a phone at school, get a pay-as-you-go phone but leave it in your locker, or use a computer at school to message (or, better yet, phone) your friend to explain.

If your dad called a flipped shit on his parents, you might want to clear the air, even though you're dad sounds way out of line and like he overreacted out of an irrational sounding need to be overprotective. I'm sure he thinks his heart is in the right place, and Cassado already gave you some tips for your family, but your friends parents might be concerned for you and possibly their kid (e.g. they might not want their kid/your friend to come to your house any more after your dads outburst). Calling or messaging him (using another device) ask asking him to relay certain details might go a long way to repairing the damage.