Renal failure or muscle strain?

It hurts incredibly bad on both sides running parallel to my spinal cord. The worst pain is about three inches below my bra line. Right now I am on the first day of the menstruating part of my cycle. I am not sure if it is due to this, a warning sign of renal failure, or a strained muscle from intercourse. What are the signs of kidney failure? How do I go about treating this (I've tried hot baths, Tylenol, a backrub from my boyfriend, laying flat)? Should I seek a physician's help?

Renal failure is uncommon. Do you have any other reasons or history to make you think that you have this problem?

Your kidneys are located out to the sides. If you reach behind you and put your hands flat on your back, that is where they are. Signs of failure would include things like urinating very little, blood in the urine, a general feeling of malaise, and edema (water retention).

There is a chain of muscles along the sides of the spine. In fact, there are several rows, going in different directions. There are hundreds of small muscles in your back. It is not usual for a segment of those muscles to get strained and irritated, and sometimes they spasm, causing more pain. The initial treatment is rest (in whatever position is most comfortable), ice (not heat, and not hot baths, this flares up the muscles and increases the spasm), anti-inflammatories (ibuprofen or Motrin, Aleve, Advil are over-the-counter versions). Stronger, narcotic pain relievers and muscle relaxing drugs are for more severe cases. As long is there are no shooting electrical-like pains going down your legs or arms or sides, and no disturbances with bowel or bladder control, then it is unlikely to be a slipped disc, resulting in nerve damage. So, an emergency trip to the doctor is not required. A person's tolerance for the pain and their improvement with the home remedies listed above will determine how soon they go to the doctor in that case.

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