I used to be like that. I am happy to tell you that you can grow out of it with time and experience. I am 23 now but when I was in my teens and earlier 20s i would say that I was really self conscious and would be harder on myself. My best advice would be to find something that gives you confidence or that you are very passionate about because when you talk about it to others it will just happen naturally and from the heart and you won’t second guess yourself. Hope this helps!