Stricken means "overwhelmed by emotion." When you saw the pretty new girl at school smiling at you, you were so stricken you walked right into a wall.
Stricken means "affected," whether it's in a good way — being so stricken by spring fever that you can't stop singing and goofing around — or bad, like being stricken by a real fever and a sore throat and the chills and. . . you get the idea. You can also be stricken by fear, like a family so stricken by fear of bedbugs that they cancelled their hotel reservation and just slept in their car.