If you have a sprain, will it burn and hurt really bad? or would a fracture hurt really really bad and burn? x-ray 3 weeks ago, doc said it wa spraine

Either: A severe sprain or fracture can produce similar signs and symptoms- pain, swelling and disability. Some fractures are not easily seen on the first x-ray and a follow-up x-ray can be necessary to see the fracture. After a skilled physical exam, an MRI is the test of choice to determine the severity of a ligament sprain. If your symptoms are not improving, then it's time to follow up with your doc.

Pain is common: Pain is normal up to several weeks or months after an injury. Usually with immobilization pain should be somewhat controlled. Rest and elevation will keep the swelling and pain at a minimum and possibly improve your symptoms. You may need a follow up x-ray. Burning may indicate a nerve injury.