Hey Teresa,
The stiff neck and other random symptoms you are experiencing are most likely normal. This can happen when the body is rapidly eliminating toxins. It could help to brush your tongue at least once a day and do some sauna treatments to help sweat out some toxins that might be building up. Also be sure you are drinking lots and lots of water. At least, half your body weight in ounces. Are you doing the 7 day cleanse and the fasting at the same time? It might just be that your body is going into overdrive from that combination and is eliminating a whole bunch of toxins at once. During my first water fast (1 week long), I felt stiff joints, dizzyness, and nausea. In my second fast, I did the enema and sauna treatment every other day and my symptoms were minimal. I've also read that while fasting, if you have some kind of illness or disease, you will go through all of its symptoms while the disease heals itself. Either way I think you're ok. Good luck and be sure to break the fast nice and slowly.