Doctors will tell you that your urine should be pale, but if you are taking a lot of Vitamin B (or eating a lot of food that is high in Vitamin B) you can get urine that is yellow for that reason alone. (My prenatal vitamins gave me very bright yellow pee.) Consider whether you are taking in a lot of vitamin B, and test the theory that it is from simple dehydration by upping your intake of liquids for a solid period of time, not just one day, and if neither of these things is it, you certainly aren't going to hurt yourself to see a doctor.