Glad you got some rest.
It is hard to sit there and not have the concentration to read, watch TV, or anything like that. Then you want to get up and do something but don't have the energy to do it. It's so frustrating.
When I'm in that situation, I watch stupid stuff on tv - nothing that I need a lot of brain power to do. A friend of mine told me that when she gets like that she watches Telly Tubbies.
She said it's amazing how much time goes by and you really don't need to concentrate and yet are somewhat entertained.
I also play computer games sometimes. Mindless games are the best. The ones where you don't have to think a lot.
I write in my journal. I have found this to be so helpful during those times as I can just get my thoughts out. They're just random thoughts but I get them on paper. It doesn't take a lot of concentration or focus.
Sometimes, I make lists. Lists of movies I want to watch, books to read, things I want to do, etc. I once wrote a list of all the qualities I love about each person in my life. Then I shared it with them, either in person or in an e-mail or letter. Basically, it kept me busy doing something and it really doesn't take much to do it.
Listening to music is great also. It can take me to another place full of memories. It can be very soothing and calming. I have an MP3 and I have all sorts of music on it.