Brief Answer:
Get an ultrasound scrotum done.

Detailed Answer:
Hello,
Thanks for the query.

Since there is no pain, it’s not an absolute emergency and we can evaluate to find out the cause.

As per your description, the most probable differentials are hydrocele (collection of fluid around the covering of testis) and orchitis (inflammation of testis) even though orchitis can be associated with pain. However, we have to rule out conditions like testicular tumors and varicocele.

As a first line investigation, you can go for a scrotal ultrasound with Doppler, an ultrasound scan can pick up testicular conditions and further evaluation will be based on ultrasound reports.

If it comes out as hydrocele it can be easily corrected by a simple surgical procedure and orchitis can be managed conservatively managed with antibiotics.

Wishing you good health. Feel free to ask further.
Thanks

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