Welcome at HCM.
I have read complete details of your question.It looks from your details that you may be having sacroiliac dysfunction.There is mild abnormality with joint at your joint in back.You may also have associated urinary tract infection
You should do following to have relief in this-
-Do strict bed rest
-Avoid bending forward.
-Do warm saline fomentation with help of a rubber bag over back.
-Get a complete urine examination with culture & sensitivity of urine.
-If possible take an antibiotic preparation on prescription of your doctor.
Hope this all will help you.
With best wishes.