Yes, this is pretty normal. Everyone experiences these random thoughts at some point...but for those of us with anxiety, we tend to take it to the next level!;p
Derealization and depersonalization are both anxiety symptoms that can make our relaity and even our sense of self warped. It is a defense mechanism and often happens in times of panic, but can happen at other times as well, when we are simply experiencing chronic stress.
Lowering your over all anxiety levels through coping mechanisms will help to prevent this. Try to accept it when it happens as something that is indicative of stress...not a more serious mental health issue. If you worry about
the anxiety symptoms...guess what? Your anxiety increases! So try some breathing and relaxation exercises to reset and feel yourself again.:)
Take care,
S.C.
You can read more about it here;
http://panicdisorder.about.com/od/symptoms/a/DeperDereal.htm