Hello and welcome to healthcare magic!!!
the pain in your back and thigh to leg could be due to a nerve
getting compressed near the exit from spinal cord
which is mostly the result of acute trauma to your back on sudden bending or lifting heavy objects.it is better you dont strain your back and take rest for a while once the pain subsides you can do a few back strengthening exercises.and regarding the pain in your testis it could be referred pain
or could be due to local cause i would recommend you consult a doctor immediately so as to be sure. A general surgeon
or anurologist would be better.