[FirstYorkie]

The trying to poop with nothing or very little coming out makes me think he might be constipated. When he does poop are they small?

In any case, what I would do is give him a little piece of raw carrot. Works wonders for constipation when Joey has had it. If that makes him too loose, you should easily be able to firm him back up by sprinkling a little cooked rice over his food.