Kate,general achiness could have many sources including allergies and depression or arthritis. I know how hard it is to get moving when you just don't feel like it. Have you tried meditation? I find meditating just 5 minutes every morning helps get me in a different frame of mind for the rest of the day. I try to focus on what I want for the day and imagine what it would feel like if I accomplish that. Most days, I'm able to focus and then have a good day. Once in a while, my brain has other ideas and the focus isn't there, but I keep doing it.

Orchid's idea of blogging is a good one. Another way to get the creative juices flowing is free-writing. Just write. Even if you have a whole page of "I don't know what to write" that's okay. It's the act of actually writing that can free the blocks.