A quick-onset headache
If the pain in your head occurred suddenly and is unbearably bad, you could have a burst blood vessel in your brain. Call the ambulance immediately.
Pain that spreads across your chest
Pain that starts in the lower back and affects the legs
If there is also weakness in your legs, loss of bladder sensation, or new urinary incontinence, you could have cauda equina syndrome. Seek urgent medical assessment.
Pain in the lower right of the gut
If there is also fever, nausea and/or vomiting, you could have appendicitis. Visit your doctor, who may send you to the hospital for surgery.
Achy or cramping pain in the leg
If the pain is accompanied by redness, warmth and swelling, you could have a blood clot known as a deep-vein thrombosis (DVT). Visit your doctor, who will arrange for you to have an ultrasound. Do NOT massage the painful area, as this might cause the blood clot to travel to your heart or lungs.