Strange disturbance

I've been experiencing some strange disturbance lately.. Like, getting the physical symptoms I usually get when I'm depressed... except my moods have been pretty stable.. I'm loosing sleep for no reason, I keep randomly getting sleepy during the day because of it and everything's just felt kind of heavier... but my mind, thoughts, and moods have been pretty neutral if not somewhat upbeat... so whats going on? Why am I loosing sleep? Why have I been so sluggish, even when I do get a full-nights sleep if I have the day off I don't really do a whole lot except lie in bed and watch cartoons (lol)... I've been trying to get more active lately, have a job that keeps me on the move a lot (admittedly cuddling cats but still, I'm usually out and about making sure they all of water, food, and love).
 
I don't feel very down emotionally, just noticed my body seems to be experiencing some sort of physical depression... since I started exercising this has lessened somewhat but I'm still loosing sleep for no reason (other than to watch cartoons apparently).