We take our dog into the garden at regular intervals throughout the day so he can do a wee. We never wait for him to ‘ask’, we just take him. He knows what to do, does his business, then comes back in.
From what you’re saying, it doesn’t really seem as if he’s in pain, he’s just trying to get your attention so he can go out for a wee.
If I was you, I’d just take him into the garden every couple of hours, get him used to knowing what’s expected of him and if he does his wee, give him a small treat when you’re both back in the house. He’ll soon get the hang of doing a wee in command.