Insecure about how I look

I'm SO insecure and I feel like I'll never stop.. I'm 16, and every other 16 year old girl that I know looks like their age, while I feel that I look much younger. When people see selfies of me, they always assume that I'm 14 or 15, and I've even gotten 13, and gotten comments like "you definitely don't look 16." It also doesn't help that I'm 4'10, so when people see me in person they probably think I look like a pre-teen. I'm worried that I'll never grow, and I'm worried that I'll never look my age.