Thanks for your query.Based on the facts that you have posted it appears that you have sebaceous cysts over scrotum
since a long time.
However this needs to be confirmed by clinical examination by a qualified General
Surgeon or Urologist
The scrotal skin is rich in sebaceous glands and hence prone to get more sebaceous cyst due to accumulation of sebum beneath the skin.
Normally they fade away without treatment however they need to be treated if increase in size or get infected.
Please consult qualified General Surgeon
for clinical evaluation and further treatment.
You may need to get them excised under local anaesthesia.