STD, Infection, Normal?

What you are describing is called smagma. It is not semen. You need to clean yourself better. Pull your foreskin back each time you urinate. Then make sure the head of your is clean and dry before you put the foreskin back in place. I am not saying that you are not a clean person, but cleaning yourself is not something mothers usually teach their sons, and dads don't think about it. Good luck.