The most common initial symptoms of testicular cancer typically include a painless lump or swelling in the testicle. While pain is not common, a feeling of discomfort or heaviness in the scrotum (the sac-like structure containing the testicles) may occur.

General symptoms of testicular cancer may include:
* A painless, firm lump or swelling felt in one of the testicles.
* A noticeable change in the size or shape of a testicle.
* A feeling of heaviness or dragging in the scrotum.
* A dull ache or discomfort in the lower abdomen or groin area.
* Sudden collection of fluid in the scrotum (hydrocele).
* Breast tenderness or enlargement (gynecomastia).

Depending on the stage of the disease, more advanced symptoms such as the following may also develop:
* Persistent cough or shortness of breath.
* Swelling in one or both legs (which could indicate a blood clot).
* Back pain.
* Unexplained weight loss.
* Symptoms resembling a testicular or epididymal infection (orchitis or epididymitis) that do not respond to antibiotic treatment.

Early diagnosis is critical for the success of testicular cancer treatment. If you notice any of the above symptoms, it is strongly advised to consult a healthcare professional without delay.