Firstly calm down. Its not
HIV related symptom.
You have a long working hours and you are mostly moving in sun. Prone to dehydration so its mostly dehydration leading to concentrated urine and since urine ph is acidic you have burning sensation
Next Steps
Firstly clean the penis opening or meatus with water after your urination, keep it clean and dry.
Increase water consumption, to 3L per day atleast. Try drinking majority of it when you are working and driving.
Health Tips
If possible connect with me to check if you are suffering from urinary tract infection for which i would have to start antibiotics