Brief Answer:
Sebaceous cysts-no active intervention required

Detailed Answer:
Hello,
Thank you for posting on HCM.
From your description its difficult to point of specific diagnosis unless a proper examination is done.
I think the 'white pimple-like' lesions you mentioned, must be sebaceous cysts.These cysts are pretty common over scrotum as it is rich in sebaceous glands i.e oil producing glands of body and sometimes due to some blockage in the duct cysts are formed.
Sebaceous cysts are benign and usually donot warrant any active treatment unless and untill it is bothersome because of size or secondary infection.
For large cysts or cysts with infection (painful/purulent or bloody discharge etc), then the best option is surgical removal by a qualified dermatologist or surgeon.

These cysts has nothing to do with the decrease in your semen volume or excessive masturbation.

Kindly get checked from a qualified urologist for the problem regarding semen volume.

Maintain hygiene and avoid tight undergarments.

Hope this will take care of your issue.

Let me know if you require any more assistance from my side.

Thank you
Dr Hardik Pitroda

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Brief Answer:
Please post some pictures

Detailed Answer:
Hello again,
I dont think there is any STD but still to rule out any doubt whatsoever, I would like to request you to post some good clinical pictures.
You can mail pictures to YYYY@YYYY with subject titled 'ATTN Dr Hardik Pitroda'
Thanks
Dr Hardik Pitroda

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