Thanks for your question, I’m sure there are some other folks who are wondering the same thing.
What I believe you’re describing is what is called pearly penile papules also known as Hirsuties coronae glandis. They are found on the sulcus or corona of the glans (the ridge-like base of the head of the penis or the neck of the penis). They look like small dome or thread-like projections or bumps that go around the underside of the penis head in one or more rows. The papules are completely normal, common to have and are at no risk to your health.
As sexual health practitioners, we see these a lot and they are very easy to identify. If this all sounds like what you have, you can be confident in the doctor’s assessment and reassurance. The papules shouldn’t cause any pain, dysfunction or open sores. If you have any symptoms, you could visit the doctor for that.
Thanks again for your question. I hope this has helped.