I think my snake is blind?

Question
HI Ken - I have a one year old Granite Burmese Python- i have had her since she was born - she is very healthy and has always been very alert - the past 2 days though she dose not seem to notice movement - every time i walk into the room that her cage is in she would always stand up when she saw me - now she does not move even when i wave my hand infront of her tank? If i take her out she acts normal but if i wave my hand infront of her eyes she does not move at all as if she dosent even notice them? Normally when i wave my hands infront of her eyes she will move her head away -  Should this concern me? and are there ways of telling that my snake has gone blind?

Answer
It's only been 2 days the snake could be going in to a shed and not see quite as well.  Could just be cold and less active inside the tank.  I wouldn't worry too much about it right now and even if she was blind snakes use their sense of smell more than sight anyways.  I doubt it's just suddenly went blind with no other signs though.