My urine is brown why?!

3 days ago i became a little sick. my eye's began to hurt badly. and my urine started to look like a dark brown. I see no red in it. today it still is brown, but im not as sick as i was yesterday. my father told me it was because i have the flu and im not drinking enough water, and I haven't been drinking alot of water. and my mother thinks i need to go to the doctor. Does anyone know if it is because im sick, or because i have an infection, or any other reasons. I should have add the fact. i didn't vomit, or have diarrhea. at dinner time i drank lots of water and after word my urine was yellow. but after 2 hours of watching tv it turned brown again.