Hurts to pee

I know most people’s reaction to this is going to be uti or some sort of std/sti. I can tell you right now it’s not an std/sti. I literally just got tested and I’m still clean. And it’s not a uti. I’ve had this issue whenever I get dehydrated it hurts soo bad to pee. Like I have a uti. But this has literally been happening my entire life even when I was a little kid. And I drink and much water and liquids as I can. Mostly water. But it seems to never be enough. It’ll feel okay for a few times or so. But then it automatically starts hurting again. I even drink a lot of water before bed. I have to pee before I have to sleep though or I literally can’t fall asleep. I’m just wondering if there’s a reason why I can’t stay hydrated and if there’s anything to help?