So very very tired

picture from Tiana RA.ti flickr

i can't quite seem to put my finger on what is sucking the life out of me...but whatever it is is doing a fantastic job. Depression? It shouldn't be, nothing on the down and outs over here. Exhaustion? Possibly, although shouldn't be, since I am not doing anything out of the ordinary. It is summer I should be enjoying the warm air, but I get home from work and just crash. I do want to sit on the swing and enjoy the warm breeze, yet I sit down and just fall asleep.
Diet, exercising, relaxing? what next...i need to correct this mental problem I'm having