[header] How to know if you have epididymitis [title] Pay attention to testicular pain that begins on one side. [step] With epididymitis, pain usually starts on one side, rather than both at the same time. Over time, it may slowly expand to both sides. 
Typically, you'll notice pain on the underside of your testicle first, though it will spread to the whole testicle. [substeps] The type of pain differs depending on how long the epididymis has been inflamed; it may be a sharp or burning pain.