it seems hard for everyone at some times. just u need to get your confidence up, and probably your fitness. lets say ur not improving much in skill, well if ur athletic ( run faster, jump higher, better reflexes) u will get steals, interceptions, blocks and can just dominate. also, for your skills, if u dont have better basketball videos then i highly recommend u get them, just so u know the right things to train. also, when there are rep tryouts for your local team then try out. they train u hard and have the best coaches, they will help u polish your game and u will learn heaps of plays, also with your commitment u will increase fast
good luck