Why do no girls seem to find me attractive no more?

well, i don't have a pic but i will try and give a precise description. I am 16 years old. I am quite a short guy at 5'6, i am well proportioned, i am quite broad shouldered and am quite athletic. I can be quite tanned, but during the winter i'm relatively pale. I have blue eyes, dark hair like a really dark brown. I have quite ok teeth, that are clean. I have blemishes a tiny bit where i used to have spots, but they have faded alot lately. I am not quite confident unless im drunk ( tut tut ) tbh i think its my height, and the fact i could not pull girls my own age either. But the thing is when i was like 14 i had girls all over me, i was seeing all the nicest girls in my school year. Then it just faded away as i got more nervous and shy around them. Know i am back! but what are the best techniques to talk to girls?