Hi I was just wondering about something. On the underside of my penis there are some bumps that kind of look like goose bumps but are maybe a little bigger. I'm not sure about this, but it seems that when I am erect they are more noticeable. Should I be concerned in any way? They don't seem to itch or hurt or anything.
What you are seeing are called Fordyce spots. They are a normal part of the body, just more noticeable now that your penis is getting bigger and the skin on your penis is getting thinner. See the following, which include some pictures of Fordyce spots so you can compare:
It is also possible that you are seeing hair pushing the skin up a bit as described in There are bumps on the shaft of my penis that look like goose bumps. What are they? But these tend to be small bumps.