Thanks for your question. When the penis becomes erect it gets increased blood flow, which then leads to an increase in its size. Since there’s more blood flow it’s normal to notice blood vessels getting bigger on your penis. However, an erection should not be painful.
Whenever there’s pain along any part of the penis it’s a good idea to see a health care provider. They can do a genital exam, which means they can examine the penis and testicles. They can help figure out whether this will go away on its own or whether there’s an issue with the blood flow to the penis or the inner layers of the penis. It’s important to let your health care provider know if you’ve had any penis injury (i.e. with sports or accidents) and if you are sexually active.
Here’s a tip on how to bring it up to your health care provider: “I get a sharp pain at the tip of my penis, is this normal?”