Be at peace with yourself dear. You need to make the decision to have some confidence in who you are. Zero confidence is just as much a sin as overconfidence. Everyone has a different opinion of beauty, and just because you don't find yourself beautiful doesn't mean that others won't. All your characteristics have no real bearing on how people will scale your beauty, it is primarily in facial and body structure where people dwell. But again, everyone has a different taste (its a subconscious genetic phenomenon, genes want to reproduce with what they think will increase the reproductive fitness of the offspring...ecology mumbo jumbo...).
The fact that you are a virgin is a very good thing. Stay a virgin...don't offer yourself up to the lustful debauchery of male (or in this case...female) scumbags! Leave you a desolate husk, they will.
Signup on a image/photo hosting website (like Photobucket.com for example). After you join (it's free), you can upload a photo. Then take the link from the photo (will appear on the lower left hand side of the screen, and copy it. Then past it to an update of this posting/quest. Then there you go :-)
First off, you're still a kid! Of course your body is still changing, and you're just starting to understand who you are, and where you're going in life. Don't be too hard on yourself. Work on the self esteem, and everything else will slowly work itself out.
However, one thing I learned in a fashion book (and I totally agree) is that the lighter the blonde (i.e. dyed platinum) the shorter it should be. If you're going to be uber blonde, it looks less harsh when it's shoulder length or shorter. it looks healthier when it's not so long.
And don't get me started on the bisexual thing. I think at that age, very few people can decide (let alone understand) their sexuality, ESPECIALLY if you've never had a boyfriend. Don't be so quick to label yourself...
Personally, being in a size 10-12 and only standing at 5'1" seems pretty (okay, really) pudgy to me. I mean, I am a size 10 (closer to being in a size 8 than a size 12) and I'm 5'6" and I weigh almost under 170.. and even then I am still not completely happy with how I look. I just can't imagine you having a good waist-to-hip ratio which is very unhealthy to have that much fat. I know it's probably not what you wanted to hear, but I'm being perfectly honest.
The main thing to work on is your confidence! You're very articulate so I'm sure you've a good personality. Your features sound nice so you should make the most of yourself. If you don't like a certain feature, see what you can do to change it and if you can't just accept it. If other people are sayin you're beautiful there must be at least some truth to it! =)