Long story. About half a year ago, I started feeling an odd pain
at the tip of the penis. At first, I thought there was no chance of STD (I'd only had unprotected sex once in about two years) and thought that it may have come from rubbing against my trousers (I live in Thailand). About a month later, a bit of pus-like discharge came out so I went straight to the hospital and had a whole bunch of tests done - gonorrhea, chlamydia, HIV, syphilis, etc. and everything came out clean.