Are you really young?
Who cares if its by yourself. Its boring no matter who you are with. Flying just blows! But if you pick a good airline, like Virgin, they have video games at your seat.
The East Coast of America is so different from California, it may as well be a different country. I've been to every East Coast state besides New Hampshire and Maine, and it feels like a foreign country to me. Southern California and Norther California may as well be separate states. Whatever you do, make sure you don't just veg out in LA. Go to San Diego or Santa Barbara or come to San Francisco, Santa Cruz, Napa, or somewhere beautiful. I suggest you drive up the 101 Freeway from LA to San Fran to get a good glimpse of California.