I have pains in the middle an lower portion of my back.when i bend over n stand i get very dizzy..what can cause this?sometimes my back feels like it's on fire

Back pain: Back pain is very common, and the sensation can be intense. Common causes include inflammation or partial breakdown of the intervertebral disks, but there are many other causes too. If you have any burning or discomfort with urination, it's important to check for urine infection. Dizziness on standing is normal if you are in pain and get up fast - but have your doctor check your blood pressure.

Lots of things: There are a lot of causes of low back pain. Assuming that this pain has been there for more than a few days then i would suggest getting in to see your primary care provider for an assessment. If you have already seen a primary care provider without getting better then referral to an interventional pain management doctor would be appropriate. See www.Spinalinjection.Org and www.Asipp.Org.

Many causes: Most commonly at your age, this would be a muscular problem. A strain of the posture muscles of the back. Physical therapy would be the place to start. If you do not improve more test would be needed to find the cause of your pain. Another likely cause from the little information you provided is a problem in the facet joints of the lumbar spine. You may need to see a pain management specialist.