Thank you for asking. I can understand the your concern. To establish a condition of Erectile dysfunction, a detailed knowledge about the problem and associated symptoms is required. Risk factors of masturbation, use of pornography, lifestyle associated risk factors, etc needs to be explored in details. Regardung your question of penis size, size of 3.5 to 5.5 inches is normal. Much of myth is associated related to the size of penis that needs to be corrected.