A cluster of blisters on the penis could be caused by various conditions other than herpes. These blisters may result from skin irritation, friction, allergic reactions, or infections such as genital warts or a bacterial infection like folliculitis. To determine the exact cause and receive appropriate treatment, it's crucial to consult a healthcare provider for an evaluation and diagnosis. They can provide accurate insight into your specific situation and recommend suitable management options based on their assessment.

If you have concerns about potential STDs like herpes or any other condition affecting your sexual health, seeking professional medical advice is essential for proper care and peace of mind. Remember that timely intervention leads to better outcomes in managing these issues effectively.