why does my ocd make me worry about my bladder so much

like whyyyyy. this has been bothering me for years and I didn't even know that other people with ocd experienced it too. i rarely ever actually have to pee, i don't even know what the fear is. am i scared to have a full bladder? why can't i just go to the bathroom when i feel i need to go. what is the overall fear here ughhhh. it's the worst before bed. i CANNOT go to sleep unless it is right after i went to the bathroom. if i end up going on my phone even just for a miinute to set my alarm or respond to a text, it is no longer "empty" and i cannot go to sleep, so i get up and go again. if ive been lying in bed for 10 minutes, thats 10 miinutes of my bladder filling and i have to go again. even if i tell myself i know i dont need to go, just having that urge and knowing its not empty stresses me out so much. i dont care if i have to wake up in the middle of the nght to pee, i think its just me wanting to avoid the discomfort i feel in the moment where i cant get a thought out of my head. right now im eating a snack, and my ocd for some reason makes me relieve my bladder right before i eat. i made my food but then my ocd reminded me that it now has been five minutes since i went to the bathroom, and that i wont be able to enjoy my snack until i go. i am currently eating my snack and i havent gone to the bathroom, im challenging it! but why do i even care???? why cant i enjoy my food or go to bed or leave the house without a single minute passing by without me going pee. some nights it takes me hours to go to bed because im constantly getting up to "pee" and i end up sitting in the bathroom for way longer than i need to because i dont even have to pee its my ocd, so i just wait and then try and go to bed and then the cycle just starts all over. sorry if thats tmi, im just ranting at this point. i just wanted to let it out to potentially some people who know what i mean.