I finally let myself piss after holding 3 liters of water for 4 hours and leaking a bit into my shorts. I was so hard it was hard to get the piss out and came out in spurts and spats. My bladder is still full it feels like but I can't get anymore out right now.
Been holding my piss for over 3.5 hours now. Yes I did leak a bit as you could see in my last post. I have now reached the hard on stage of holding. When my bladder is at max capacity I get a hard on which also lets me hold on longer!