How should I have handled this situation with my dad?

What you did was right. It doesn't matter how old we are, 17 or 70 we should still respect our parents and their wishes.Besides your dad may be right,better safe then sorry. I know that having controlling parents can be a pain in the neck (my mother is a very good example) but as long as you are living in there house and completely deepened on their allowance you are not considered as an adult. Besides,your dad doesn't sound that bad,the fact that he bought you those tickets means that he does want you to have some fun and that he may even realise that he is being overprotecting at times but just cant help it. Cheer up, you might miss Coachella but maybe later you'll see something even better.