I would go and see the doc now. I have come across this twice in my life. Once was a friend of mines grandmother had the same problem and she ended up having surgery because something was wrong with her esophagus. The only other time I have come across this problem was with myself a couple years ago. My doctor had me on trazodone (a sleeping aid) which about 15 minutes after I took it my muscles would be so relaxed that I could not swallow. If you are on muscle relaxers or sleep aids then you could be experiencing what i did.. if you are not then you should call your doctor.