I sometimes wake up in the middle of the night with severe burning pain in my throat. What can this be? I'm fine during the day.

Reflux or dry mouth. You may be breathing through your mouth at night, which causes drying of the throat which can hurt. You also could have GERD (gastroesophageal reflux disease). Don't eat within a couple of hours before going to bed, avoid spicy or greasy foods, caffeine, alcohol & nicotine before bedtime and elevate the head of the bed 40 to 60 degrees. Sleep on right side. .Get checked by doc to be sure.
Reflux possibly. You may be suffering from a condition of REFLUX whereby stomach acids are traveling outside the stomach into your esophagus. This usually occurs due to the sphincter at the junction of the esophagus and stomach is relaxed more than it should be and acid escapes. Sleep propped up on a couple pillows and you'll solve the problem for the time being. You'll need to see a doctor to get definitve tx.