tired like an onion

Layers of fatigue go in layers like onions. The outermost layer gets tired and is rejuvenated with a good night sleep. As the fatigue sinks further and further through the layers it doesn't seem to matter how many 'good night sleep's I get -- I'm still tired - increasingly so. I don't mind always having something to do, it's the always-having-something-to-do-under-pressure that is getting to me.