im no expert at auras, i cant see them myself. but what ive been told is that the aura is constantly changing, due to your mood etc, like you said. but some colors in it is more consistant, they dont change as often. they symbolize your base personality, your karma etc. so to a certain degree, you could say yes, you can see the karma in your aura. those consistant colors may also change through your life, as your personality changes and your karmic debt increases or decreases.