I know exactly how you feel! Thats so strange... I suggest you go to the doctor. anything that messes with your sleep schedule and the way you eat is worth getting checked out.
It doesn't sound like an eating disorder of any typ, you might want to go get it check out though but a lot of people go through this kind of stuff as the grow up and hit puperty and growth spurts, your matabalisem is just changing
It doesn't sound like bulimia, I think you should go to a doctor in case its something to do with your tonsilitis. Just try and vary your meal sizes each day and you might go back to normal.
I suggest you go to the doctor. anything that messes with your sleep schedule and the way you eat is worth getting checked out.