I need help boosting my confidence!!?

[Kurt Dunn]

I'm 15 years old and in high school. I'm not the most popular guy but I manage to get along with people. I used to be more popular when I was younger and I talked to more people. Recently though I stopped talking to people and I've become more shy. I don't know why but i'm becoming more shy the older I get. I used to talk to this girl a while ago and we used to be into each other. I have since stopped talking to her (I don't know why) but now when I see her I get shy and never talk to her. There's like this awkward tension. It's like that with a lot of people. I must add that I'm a little bit complexed about my looks, I have quite a big nose and I'm embarrassed to speak to girls. I am worried that they won't like me. Once again, I used to be more popular with girls when I was younger and more used to think I'm attractive. I don't know why that's changed. All the girls that told me they fancied me no longer talk to me. So I'd like to go back to the way it was.. talk to more people and have more friends, and not worry about my looks. Please, any advice would be greatly appreciated. Thanks.