Hi ! Possibly your doctor who has examined you clinically is right. The most probable diagnosis tends to be a epididymo orchitis
which is a benign condition and occurs due to prolonged standing ( if your job demands it ) or due to lifting of heavy weight apart from repeated trivial trauma which frequently goes unnoticed.
You will be advised to wear a properly fitting scrotal support and take some antibiotics and anti inflammatory drugs by your treating doctor, which possibly will cure your condition. Also you have to take rest for the duration. Apart from this, if you belong to a tropical area, then filariasis
has to be excluded by your treating doctor. Wishing you an early recovery.