What can cause severe back pain?

I have had back pain for almost a year now. I am only 15 years of age. I used to do gymnastics but now I can’t even touch my toes. Some movement are so painful it makes me cry. This came on suddenly. WebMD mentioned Spondlitis? But I don’t quite know. Help?

You could have slipped a disc, or number of things your best bet is to go see a doctor to get the exact nature of your injury.