So I am doing my homework for my painting class. The Assignment is to paint an egg using titanium white and ivory black (both W&N artist's oils). I was mixing up a value to make the ground darker, the value is about a 4, when i accidentally put to much Turpenoid in the paint and i noticed when i put it on the canvas that is was much warmer and yellower then the surrounding paint. I thought maybe it was because the lighting in my room is very warm and yellow and the extra turp made it more reflective of the light, but I don't know. Is this normal? and if so what causes it?