Have you ever seen your Dr about this? If not, I recommend that you do. I wish I could tell you what's going on but I'm not really sure. You say as long as you can remember but can you say how long exactly?
You're not circumcised so that may be the problem. Do you have any problems with your foreskin, is it very tight? If so, it could be causing constant irritation to your urethra when you pull the foreskin back.