Why do I keep waking up in middle of the night feeling like I swallowed something and am choking in my sleep? This is happening more and more frequent

At your age. At your age I think that this may be due to reflux of acid from your stomach suggested by the your statement that this is happening at night. You may be at risk of aspirating this into your lungs . Most people with this degree of reflux also have "heartburn" . A number of other problems however may be causing these symtptoms.