Why do i feel broody at 16?

Before you jump NO i aint having a baby or planning on one for at least another decade,i dont have money to support a baby, dont have a job and i dont have a relationship! dont worry :) plus my parents would KILL me anyways ..."/..My question is Why do i feel like this at 16 ?..Why when i see a baby in a pram i just keep staring at it? and Why do get this feeling this weird feeling inside me when i see one? im 16 why am i being this way ive been like this for a year!! No i aint a crazy baby lady whos going to snatch one away.The thoughts of birth makes me scared even..WHAT UP WITH ME? ...im open to any advice! and thanks for your time : )