What will help my back?

i know I'm 13 and i shouldn't have back pain but ever sense a car accident to were our truck flipped in December anyway back to my point i went to the doctors and they didn't know whats wrong figures right i know so they gave me these rules of stretching and crap like that i told my mom that i need to go to the chiropractor aka the snap crackle and pop doctor but we can't its too much money so maybe u guys can help maybe help me what stretches anything cheap and the pain is up and down on my spine and having my dad crack it does not do the job. Thanks 4 reading! -sydney