What Causes Shooting Pain From My Lower Back To Testicles?

I have an issue where my back will go out after working with it or during intercourse and after it goes out, it takes me a while before I can get back up and move again. It feels like lightning has shot through my spine and after I am able to move around, it continues to hurt for a week or so. The strange part is that the prolonged pain is in the small of my back and shoots down to my testicles and it feels like a pulsating pain. I have tested negative for STDs.