That sounds about average to me. There are lots of 'ways' of making it larger, but most of these ways are spoofs (penis enlargement pills), or extremely temporary and risky (Ie: penis pump). You're more than welcome to try them for yourself, but I think penis size is a genetic thing (or surgical, but that's time consuming and painful/risky as well)

Hey dude, nah seems alright tbh because im the same size and ages as you and ive never had any complaints. its different if its 9" or like 2"! No you can naturally go your penis, you should be fine just dont be so hard on yourself man.