I have had this for a bit over 2 years as of what i can remember.
It gets much more swollen and red after masturbating.
I started cleaning under my foreskin about 5 months ago, and I’m soon 16, so i have gone most of my childhood life without cleaning under my foreskin, which is most likely the cause for this.
This is what it looks like around 2 hours after masturbating.