Hey, Lifesaver, no big sweat on the car...
Trust me: it is no big deal. Just make sure that
1) you don't go crazy and buy a car with payments that will strap you down (my friend bought a car with $600/mo payments and now can't go out to eat, buy new clothes, go on vacation... but he's got a killer car.)
and
2) try to finance with a local credit union... cheap interest rates are a godsend. Your payments are less, and more of the payment goes towards the principal balance (which makes it less "upside down" should the time come to trade it in)
Seriously, don't worry about the whole "big responsibility" thing, it is just one of many (MANY MANY MANY) steps to becoming an adult.
Best of luck
------------------
Faced with the Divine, I was asked; "What one gift do you seek?"
I answered ever so meekly; "I seek Honor, Truth, Integrity, and Wisdom, yet those are four. How am I to choose?"
The answer came as a pounding whisper; "The four you seek are but one. I grant thee Compassion; for without it the four make none."
Author - me