Ever feel TOO tired?

sometime when we sleep in for longer we feel more tired and it is only until the next day that we feel the benefits, I usually get up at 6.30 - 7.00am and go to bed at 1.00am and I have been used to this for a few years and my body is use to it, but if I sleep in until 10.00am I feel awful and feel all i want is to go back to bed and have more sleep.

I do that too when I have had enough sleep, or think I do, but I realize later it is the 'deep sleep' I miss out on during the night and once awakened, going back to sleep I am so relaxed I slip into very deep sleep and just be way too tired hours later. It is not the healthiest way to get our 'rem cycle sleep' but the easiest if we don't have to work everyday and be up by dawn!