Hello sickandtired,
I'm sorry you're going through such a rough time. With the constant stomach pain and insomnia, have you thought about checking in to intestinal parasites? Also, as far as a blood test for gluten intolerance, it doesn't always show up. You might want to try the gluten free diet for one month and then reintroduce gluten foods to test for a reaction.
Here is a link to an article I wrote about parasites that might help you:
Cure Intestinal Parasites Naturally
I hope this helps you.
Jaime