Believe it or not, it is something very common for those of us who are circumcised. It happened to me as a child, it was because I played sports and used to walk naked on the beach.
One of the functions of the foreskin is to prevent any infection from entering the meatus or from being injured by friction with clothing. Not a single doctor in the US explains it to you, If you get an infection in your foreskin, it turns red, something similar has already done its job.
Otherwise, the only way to protect your body is by closing exposed places, such as in this case the meatus.
1) My first time with this problem was on a trip to the beach, wrestling, swimming, I won't be able to tell you when it was but something entered my meatus that is normally expelled by the body when urinating. But in this case it was not enough and it began to inflame my meatus to the point that it started to burn. Luckily with a little medicine I solved it.
2) The second time was when I started playing football, the movement caused friction with my clothes, which caused a burn on my glans and, above all, my meatus, causing it to close a little. Then my dad found out and they suggested that I use cream like Vaseline or put a protection on my glans.
3) The third was because we started using a different soap and it caused irritation.
The funny thing is that I asked friends and most of them told me that they had the discomfort but never went to the doctor or some of them had to have surgery when they had problems urinating.