what is this?

Warning, rambling feelings that I'm trying to process ahead, proceed with caution, and don't read too much into them, just sending it out into the world...

I'm in a funk... I don't know what it is or how to shake it. I have a lack of motivation, a lack of caring. I still want to do things, I just feel like I have no energy to do them, it is a very frustrating thing for me. I feel like sleeping more than I should, I want to do nothing, literally nothing! I still love my life, love my job, my husband, etc... I just wish I knew where this feeling was coming from and how to make it go away. I have the desire to do other things, its the I want to do ______ but when it comes time to do it, all of the sudden its gone. *sigh. I want out of this funk. I want back to my normal life, where I'm full of energy and ready to do anything. I'm sure it will pass, I am still able to get done what needs to be done... I just wish I had more motivation. What is this feeling?