I have lower back pain on the right side!?!

I'm 15 years old and I recently had major lower back pain while playing football with no reason, i just got it randomly as i was running, its been 10 days since the pain after football. Its now better but when i wake up it hurts quite a lot! And i can still feel it when i stretch/ bend to get something. it seems like its just on the right side of my lower back!
I need help! what can I do, apart from doctors as they only give pain killers!