Brief Answer:
Infection

Detailed Answer:
Hi

Thanks for asking.

Masturbation is a normal phenomenon having no effect on the overall health of the individual either sexual or otherwise.

Pain , swelling in the testis can be because of infection or inflammation of the testicular and epididymal areas called epididymoorchitis.

The condition can be acute, although in your case it looks like a chronic condition.

It can be diagnosed by ultrasound of the testicular area,Additional tests may be necessary to identify underlying causes. In younger children, a urinary tract anomaly is frequently found. In sexually active men, tests for sexually transmitted diseases may be done. These may include microscopy and culture of a first void urine sample, Gram stain and culture of fluid or a swab from the urethra, nucleic acid amplification tests (to amplify and detect microbial DNA or other nucleic acids).

Thanks.

Please let me know if you need more information.

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Brief Answer: XXXXXXX Medicine specialist

Detailed Answer:
You can look for the local yellow pages to look for XXXXXXX medicine specialist in your area.

I think only after the proper investigations/ultrasound any further advise can be given.

Thanks.

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