I Am A 61 Year Old Male In Great Health

I am a 61 year old Male in great health I had a varicose vein sealed in my left testicle when I was 22. I get some pain in the last ten years around that testicle. I got checked out and the urologist sad it was fine and it might always have slight pain. I noticed last week that there was some blood in my sperm I have recently been having more sex. What could it be