### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
Im prone to bladder infections. If i dont pee right after sex Im almost promised one. My Dr. has given me antibiotics to take in case i cant pee (one right after, one 12 hours later) to help prevent them. Lately my pee has gone from being cloudy (and painful which are my usual symptoms) to very VERY dark brown in colour and almost metalic in smell - its a really STRONG odour. Also, sometimes when im done air actually comes out of my urethra (its NOT my vagina - I KNOW that sensation and that only happens to me during sex) and Ive never had this happen before. I have some lower back pain which worries me about my kidneys. Is this a major cause for concern?

### output:

Hi and thanks for sharing your question with us on Chat Doctor. Yes, bladder infection can cause referred pain to the lower back. The color and smell of your urine is very worrisome - I am worried about bleeding in the bladder as a result of infection or worse, a fistula (connection between the bladder and the colon) or even a tumor. The air coming out of the urethra (pneumatic) suggests gas-producing bacteria or gas from the colon. You need to urgently see your regular doctor and have them work you up - urinalysis, culture and sensitivity to identify and treat the offending organism renal profile to review kidney function ultrasound and more in depth imaging studies to determine if there are diverticula (outpourings in the bladder) or a fistula as a result of all the recurrent infectionsReduced or impaired kidney function does not cause lower back pain - the kidneys are located just below the ribs. However, you are at real risk for acute kidney infection, and I am concerned that the recurring infections have damaged the kidneys. I am afraid that you have a major problem on your hands. I know that this is easier said than done, but I urge you to remain calm, educate yourself and consult your regular doctor so that he can help investigate you and refer you on for comprehensive care. Do act quickly - please take care. Chat Doctor. 