Hi,
Just adding to the reply of Laneskid1955, after daily bath, dry the affected spot with a towel and apply any medicated powder or an ointment like neosporin ( if you are not allergic to its components and you have used it in the past ) till it clears up. It appears to be a bacterial infection due to sweating and poor hygiene.
Solace
You need to shower every day! Swaerign all day long and then having sex with your wife,,,,,you need to shower and clean up your privates, Once a week just isn't going to cut it. Unclean skin is a breeding ground for bacteria and germs......it explains your red maybe irriated spot on your shaft. "Crawling around buildings all day" Crouching or crawling can cause testicle pain.....maybe a jock strap to keep the boys in on tight spot...instead of pinched in the seam of your jeans or jostled about