Suggest Treatment For Back Pain After An Injury

Two days ago, I was carrying my younger brother on my back when suddenly he jerked backwards and my spine bent in the backwards direction, i would say as far as it could go without breaking, needless to say there were very loud cracking noises, but i know nothing is broken because i would be in a lot more pain if that were the case. Now I am in a lot of pain whenever i have to lean forward and back in the midback and lower lumbar areas of my spine, I think that it is the muscles around the spine that are causing the pain, like how you are sore after chiropractic adjustment, but i'm not sure. What can I do to help the pain without going to see a doctor?