Hi Dr Yesterday I Was Going To Lie Down On

Hi Dr
Yesterday I was going to lie down on bed and suddenly what happens I was not able to move. I have a series pain in my back. Iwas not able to move my body. Than gradually I rubbed and take the medicine for muscle relaxing. Than I feel fine. But still I have a slight pain there I am not feeling comfortable. Dr I want to know about this and what to do now.
Thank you