Brief Answer:
as described below.

Detailed Answer:
Hi.
Thanks for your query, albeit short and specific.
Noted the history of heavy pains in testicles and bulges too.
Please give additional information for me to assist you better:
Since when have you got the problem?
Any history suggestive of urinary tract infection like burning, frequency, pain or bleeding
?
Is the pain on one side or both sides?
Is the skin red and inflamed?
Any history of trauma?
Any history of risky sexual acts or unprotected sex?

The most probable cause is:
Epididymo-orchitis.
Or torsion.

This can be confirmed by:
Ultrasound and color Doppler.
Clinical evaluation and examination.
Tests of urine and blood.

Once diagnosed, treatment will be specific.
For example if there is infection, antibiotic cover along with symptomatic treatment for swelling and pain.
Scrotal support.
If torsion then emergency surgery.
I hope this answer helps you.
Please feel free to ask for further relevant queries if you feel that there is a gap of communication.

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