I would see your Vet ASAP, it's strongly possible that If he is not Fixed/Neutered that his prostate has grown very large to the point were it's blocking the bladder so it becomes harder to urinate for your dog.
NOW it may not be that it could be something else,
BUT your pets profile has Not Fixed and he's 10yrs old. that sounds like a classic case of enlarged prostate.
the best thing for that is to get him fixed,& in a few months the prostate will shrink .
I hope that helps you.
Regards, Barry
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