From your description it appears that you are suffering from a stricture urethra
accompanied by back pressure changes and sepsis
. I would suggest the following,
1. Go to a surgeon and get a suprapubic catheter introduced. that will drain the bladder better and reduce sepsis.
2. Undergo bladder washes daily untill the urosepsis clears as evidenced by clear urine coming and abscence of systemic symtoms.
3.Avoid per urethral insertion of catheter as that will cause more harm than good.
4. Get a contrast study to determine the length and severity of the stricture. This will dictate the surgical procedure to be performed.
5. Continue with a course of urinary antibiotics.
6. Monitor renal function periodically.