well i am a nurse also palpated my spermatic cord an everything checks out, no feeling of bag of worms on palpation or a penile discharge. one sexual partner an we use condoms.
A urologist would treat you for this. It is likely epididymitis, which just means inflammation of the epididymis. Men also get hydroceles, spermatoceles, and varicoceles, and these four conditions are the most common problems men get in their scrotums ( I worked for a urologist for 7 years). Occasionally men also get sebaceous cysts, but they are close to the skin. None of these are cancer, which should ease your mind.