Brief Answer:
Possibly an infection.

Detailed Answer:
Hi,
Thank you for using Healthcare Magic. Warm testicles associated with soreness may indicate an infection especially if there is a discharge from the penis.There are a number of infections that could cause these types of symptoms. Some of these are sexually transmitted infections and some of them are not.
I would suggest you need to see your doctor to be examined so that a definitive diagnosis can be made and possibly antibiotics started. Your doctor may want to take some blood or urine tests to identify an infection.
If you have pain in one of both testicles that is very severe, you need to see a doctor urgently and you should go to the emergency department promptly.
I hope this is of help. If you have any further questions, please do not hesitate to contact me.
Regards,
Dr K A Pottinger

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