A few points:
1) having or not having relationships often has little or nothing to do with your sexual orientation. Plenty of people don't have boyfriends during their teens (personally, I didn't start dating until I was 19), and that doesn't make them gay. Same goes for friends; it's not how many you have that determine your self worth. Think of it as quality, not quantity.
2) finding women pretty, or wanting to look like them, also doesn't necessarily mean that you're gay. I find lots of women attractive, or wish I could look like them sometimes, and I'm decidedly heterosexual.
3) however, if you think that you might be gay, or bisexual, it's not the end of the world; it's just who you are. And, it's up to you to decide what your sexual orientation is -- none of us here can put that kind of a label on you.
We've got some articles that talk about homosexuality and bisexuality that you might want to read for more perspective on this.
The Bees and...the Bees - A Homosexuality and Bisexuality Primer
We also have a whole forum on orientation and identity further down the board. Check out some of the posts in there -- you'll find lots of people asking the same question you have. You're not alone. Don't worry.