Pain in mid back left side that rotates some frontwards.started as pressure month ago. progressively worse.no uti,cystitis,or blood in urine.causes?

Time to get checkup: Any pain that persists and gets worse over one month, requires medical check up to find its cause. I assume that you have seen a doctor who is looking into possible causes. Since UTI has been ruled out, I would focus on structures located in the left upper abdomen like Kidney, spleen, paraspinal muscles and spine itself. If the pain is more than mild, I would consider doing a CT scan of the abdome