TOO horny!!!

So I am 15 years old, gonna be 16 in 2 months and well I tend to be horny... like really horny and I also already kind of want to have sex already but the thing is that I'm chubby and I know that's a main reason why I haven't had sex which in a way is a good thing but like I said I'm horny and I just can't help it... i do masturbate a lot!! Like almost everyday and at first it was helping but now all I want is sex... I don't know what to do... I'm also really self conscious and I hate that about myself but yeah is there anything you guys can advice on anything that can help me not be as horny also sex toys is out of the picture since I share a room with my sister so yeah