Can a person get pregnant without hitting pubrity and age 12 and a half?

i feel like somethings eating off of me my stomache is getting bigger and before like 2 weeks ago i had blood in my urine an im really sleepy and am always really hungry but dont want to eat sertain food cuz some i puke up or it makes me sick. my pants are starting not to fit me my stomache been growing since october and is now startin to make me worry..my stomache feels like somethings always moving ..my stomache is bigger that my now and im only 12 so im a b in size..woman please help and only serious answers..others get a life.