Hello, You are suffering from a painful pea sized lump on the testicle. It also get swollen from time to time. You are suggested to get clinically examined by a urologist / GP. Your symptoms may be indicative of serious health conditions, testicular examination to evaluate the lump is a must. Although rare, any abnormal lump on testicles must be checked to rule out testicular cancer. Most of the lumps are harmless. Other signs noticed like if the lump is growing, any associated abdominal pain or any lymph node swellings in the groin (inguinal) region may be indicative of varicocele or epidydimal cyst, etc. Scrotal skin has sebaceous glands which may get infected or blocked and present as small lumps in the skin. These sebaceous cysts may get painful and pus filled at times. Varicocele may present with mild dragging pain. Small varicoceles are usually left alone. Surgery is required in cases of large & symptomatic varicoceles. Hydrocele is often painless but will give discomfort on getting pressure. Hydrocele occurs due to trauma, infection or cancer and should be examined. Surgery may be required in enlarged hydroceles. Testicular cancer lumps are not common, but testicular cancer is one of the more common types of cancer among males. Get examined, diagnosed and treated without delay. Neglect may cause the worsening of the symptoms. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician