Part of becoming a man is that some girls will stop calling you good-looking even if you are. Young boys, especially those who look more like children rather than young men, are considered cute and harmless by girls. Girls are not afraid or intimidated by them. That's why you'll often see 16-year-old girls treating young boys like little babies. Girls will call these 10-year-old boys cute and will sometimes even kiss them, buy them ice cream, and take them shopping with them. When I was ten and eleven, a lot of older teenage girls would even ask my mom if I could go shopping with them. Sometimes I got some innocent action out of these girls (such as touching their boobs or watching them change), but these girls took me out because I was, at least in their opinion, harmless and not yet a man. They saw me as a teddy bear, and that was fine with me at that age.
Once I got older, however, I realized that I was no longer a cuddly boy so girls stopped treating me like a baby. It was up to me to catch their interest in other ways. I was no longer going to attract them as a boy but as a man. Once you realize that you're a man and no longer a boy, you won't expect girls to treat you like a teddy bear. Girls are cautious with men so don't expect girls or women to be so open with you any more. You must attract them through a combination of presence and looks. Your presence is basically how you carry yourself and the status you have obtained as a result of your achievements (be they in sports, academics, student government, etc.), Your looks are not as important as you think. At your age, everybody is extremely self-conscious, so don't think you're the only one who feels the way you do. Even the hottest girls think they're not so hot sometimes. Anyhow, look your best but don't be obsessed with your looks. Eat healthy, get lots of sleep, have a positive attitude, hang out with cool and respectful friends, and exercise (but not obsessively).