I am 16 years old, I masturbate a little while sometimes , which is usual in our age, I noticed little 4 bumpy small dots on my Penis Rim when i open my foreskin , they are only 4, they dont hurt, dont itch , dont secrete anything, seems like inactive things. It is usually unseen during normal conditions when my penis isnt erect, but when i masturbate, they are visible, I dont know what it is, They arent big either, small 4 dots thats it. Can anyone tell me what it is exactly ? and if possible show me a picture ?