Hello,
As you are very young, back pain at this age is not good. I suppose this could be because of wrong sitting position, lifting of stuffs in improper manner, too much traveling on your bike, obesity etc
Next Steps
I will suggest you to start doing regular and basic exercise. And while lifting of heavy stuff from ground don't bend directly from your back, bend from your knees and then pick up the stuff. This is correct way for it.
Health Tips
There is no need to worry, by doing the above mentioned things with our medication you will get cured. If you have any questions related to it, you can contact me online or offline. Tc.