What Causes Penile Discomfort Despite Clean Blood Test?

Hi

I am a 50 years old married healthy male, recently I have been having this penile disconfort. I have seen an urologist, he does not think i have any of the illnesses that can cause penile pain like prostatitis, my PSA is 1.3 my urine is normal also have a complete blood test taken, it shows no indication of infection. I am worried a bit. can you please advise. what could cause this.