What do incubation stage me?

If a child have been coloring and drawing shortly sfter she complains of headaches and her eyes feel sleepy?
1.amblyopia 2.myopia 3.hyperopia 4.strabsimus

this answer i just don't know !

http://www.google.com/search?q=%22incubation+stage%22&ie=utf-8&oe=utf-8&aq=t&client=firefox-a&rlz=1R1GGLL_en___US379

and

http://www.answers.com
Look up each term here (amblyopia, myopia, etc.) and decide which one fits.