permanent feeling

Hey! I am a 24 years old girl with no previous health problem. One day in February 2023 I experienced a permanent feeling that I had to pee with no relief after urinating. I have this feeling all the seconds of my life since that day. Every day is the same no flares.I remember having anxiety and exhaustion due to my exams before this appeared. Two days before I hold my pee for around 6 hours at a road trip. I did all the tests. They first found some white blood cells in the urine but never a microorganism. Urodynamics,cystoscopy,ultrasound,blood tests, cultures everything is normal. The doctors are talking about bladder hypersensitivity but all the medications they gave me did not change the feeling. The only time that the feeling lessens (not disappear) are during sex and when I have pain in the pelvic region such as stomach bug or period pain. It is very difficult to live with this and I am desperate. I cry every day that this is stuck with me forever. Do any of you had an experience like this? I dont know what to do. I blame myself that I did something wrong and caused this.