What Causes A Red Bump At The Bottom Of The Urethra?

I have a red bump at the bottom end of my urethra. It looks like a small drop of water and it's red. It doesn't hurt or nothing. It looks like it got barely bigger than a few days ago. I'm not circumsized and back in elementary I had to go to the doctor because I got an irritation due to not cleaning good enough. I'm 19.