Why Won't My Sperm Shoot Out? I Have Always Been

Why won't my sperm shoot out? I have always been able to have my sperm shoot out in the past without a problem, but now it just dribbled out. I tried waiting a weak to master are but even then it dribbled out. Also a very slight pain/discomfort in the tip of my urethra started at the same time as my ejacualtion issue. What is the problem and how can I get my penis back to its former glory.

P.S. Just thought I should add it does NOT hurt to pee or ejaculate, it is just a slight sting in top of penis