Hi I'm A 15 Year Old Girl. I Have Been

Hi I'm a 15 year old girl. I have been experiencing a pain in my lower back since last week but I ignored it. Till recently my left leg has been aching so today I put a heat patch on it now it's gone but a really bad pain started in my lower back again but this time it's my right leg from the lower back to the toe and it hurts when I stand walk sit or lie down. What can it be. Please I'm concerned.