You are feeling much better today. Your headache and nausea are gone, and your feathers have even begun to grow back, in a wonderful new colour.
You are not logged in. You can continue playing without logging in, but until you do, your game data will exist only in RAM, lasting a day at most, to remind us that all states of matter and energy are temporary.
If you log in or create a new account, you can permanently save your high scores, achievements and unlock points, proceed further in the game, and hide this dumb notice.
Well, by "Permanently," I mean "I'll put it on the hard drive." Nothing is truly permanent.