Difficult to say without examination.
EpididymitisEpididymitis, a cyst or testicular cancer can all be possible.
I would consider a urinalysis to evaluate for infection as well as obtaining a scrotal ultrasound. The ultrasound can evaluate for the possibilities listed above.
These options can be discussed with your personal physician or urologist.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
http://www.straightfromthedoc.com