I seem to be in the wars, I injured my foot 8 days ago and it has an infection in it so I am on antibiotics and struggling to get around with crutches. I went to the toilet this afternoon and all of a sudden I had a tremendous pain in my left testicle as though somebody had kicked me really hard. I stayed sitting for about 10 minutes and the pain in my testicle eased but it went into the middle of my back and hasn't gone away since. I am sitting in my armchair at the moment with a heat/massager on my back but it is still really painful
It is possible that you have put your back out, the pain from this can be felt in the testicles. if it really worries you then get it checked out but with a bad foot you are probably not distributing your weight evenly and this can put pressure on your back.