What lies beneath?

Another in my series of 'under the water.'
Been home today relaxing (well, more than usual) as I had a bad night, which for me is almost unheard of as my friends, with whom I have shared a room will agree!  I normally hit the pillow and am away.  Last night I tossed and turned, turned and tossed and eventually at 1.00 am gave up, came down and made myself a cuppa.  Back to bed and slept through until gone 0800 hrs, but am still yawning!
Thought this fitted well with the wide theme of Blue.