Are you or anyone in your house smokers? This can be a prime culprit for this, try to sleep with a window open (not easy in this weather i know) and make sure you give your eyes a good clean before you go to sleep even invest in an eye bath if you find it so uncomfortable in the mornings.
No, nobody is smoking in the house. But I'd just like to
re-iterate thats its only when I get up EXTRA early that it happens. I had to wake up about 3am recently to go on holiday and my eyes were stinging for hours afterwards.