from the description of your pain it seems that you have sprained your spine specially the lower [lumber]spine and may be some displacements in the spinal column in that region causing pressure on nerve
roots and giving rise to pain and other features as described by you
Please get consultation /check up from orthopedic surgeon and get investigations as advised and treatment .
For the time being take painkillers like powergesic tab 1 tab 3 times after meals .take rest and avoid further strain till you get it checked
hope you be all right soon