Hi honey...I posted a similar question not to long ago about naps. I always fall asleep in the afternoon(unless I am rock climbing or pouring concrete...LOL!) because I get so little sleep during the night. I feel HORRIBLE when I wake up after sleeping an hour or so. My pain is ten times worse, and the fog is unbelievable. I try to stay awake but I can't unless I am out somewhere. I don't know why this happens as it would seem to me that our body needs the sleep. I am just like you...I feel worse after a short cat nap then I do when I wake up in the morning.
I take a short rest period, late morning, where I get my whole body up on the couch and close my eyes for a short while. Late afternoon I almost always take a nap- whether it's a half hour or more, it's the only way I can make it through a day. After my afternoon nap, it does take me awhile to get moving again, but so far the benefits outweigh how I feel when I get up.
I'm like Donna, unless I am out and about, my body and brain need the rest.