Looking for some advice

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.

hows his feeding response ?

Do you hear any noise when he's yawning? Any signs of an RI? I trip to the vet may be in order.

He might just be being lazy.
You know your snake better than us, but I wouldn't worry too much. If his breathing is fine and he's not flipping out and being aggressive at you, I'd just let him be lazy. Also, temperature change and mating season, etc can cause changes in periodic activity.
I wish you luck and hope it's just nervous parent jitters!

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