peeing with an erection is incredibly bad for your health. There are special valves to stop sperm mixing with urine as urine contains many dangerous chemicals. When you force out a pee during erection morning wood or not there is possiblilty the valve could break and the urine actually travels backwards into the testicles and you need it surgically removing
i know you probably think this is far fetched but it actually happens and it can hurt quite alot i heard too. I only know cos i had to study part of it as my biology coursework at college