When you said blue, I thought you meant BLUE, as in underwater blue, which happens sometimes with crappy labs and crappy scans. What you have is totally normal. There is a color cast on the subject because none of the light that is illuminating her is white light, or even close to it. The day looks a bit overcast, which changes the color of light significantly (as does simply being in the shade). Additionally, most of the light that is lighting her is reflected off of things that are not neutral grey, white, or black, which colors the light even more. I'd suggest picking up a basic color photography textbook, such as the Henry Horenstein one. They are cheap, and are highly recommended place to begin your learning of color photography, unless you want to piece together your knowledge bit by bit over a long period of time, with many disappointing results and much wasted time spent filtering through the shortcuts, rules of thumb, and other pieces of crap information that are given to you over the years.