HELP! BROWN BLOOD

I'm bleeding brown instead of red! My period was five days late, but I still had horrid cramps and was hungry as well as emotional. My period is brown with some small swirls of red and there's brown discharge and lining as well as brown clusters. I'm very confused! I'm thirteen years old and I had early puberty if that helps??? (I've never had sex so I'm not pregnant) Dose anyone know what this is!?