They say to listen to your body, but based on your post above, I would say you are not getting enough food into your body. A weight loss of 11 lbs in 7 days is extreme and most likely mostly water weight, but the feeling of nausea and lack of appitite that you describe "ain't good."
You may have a food sensitivity in the background that is wreaking havok on your digestive tract, so you probably should start by eliminating things and seeing what is doing what.
Dairy and eggs are both allergens to many people. So my vote would be to skip these two for a bit and see what happens.
Try focusing on simple veggies and grilled meats to start, include a few starchy veggies like sweet potato too.
"I am a member of PETA...People Eat Tasty Animals"