I have a 5 1/2 ball python who is 11 years old. Up until recently he eats good and is very active, in the last week he has been acting strang. He has been yawning a lot, laying in his water dish a lot, very inactive. He won't eat and all he does it sleep and when he is active he doesn't move very much and then lays his head down. I have had him for a long time and don't want to face the fact that he may be getting to old and just tired. I have checked for mites nothing his temperature and humidity is good. Looking for advice.