Best time to go emergency vet?

Not sure what to make of today so far. He wanted to go to the beach this morning. we went to the local dog area up on the bluffs and he only used his cart to potter around and do his business. we did the rest in his wagon and he had a great time watching all the people and dogs. After getting home, he only ate a few bites and then refused the rest. He has been eating really well for me (at least half of what I make for him) so I am really confused. If he doesn't eat his dinner, I can try some appetite stimulant (we have a few doses leftover from his hospital stay).

 

He ate!
I am really worried about him getting depressed, so I am trying to get him out as much as possible even is he isn't actually active.
It has to be so hard on him, falling down so much
He is really tired, on our stroller walk on the way back he was almost always laying on his side.
I guess just being in the wagon and being pulled was a lot for him.
I am keeping an activity journal now, so I have a better idea of his hopeful progress.

 

Today Gavin ate his kibble from his bowl! I always have some out for him, but it's been in a different bowl closer to his dog bowl, and he never touched it. Today, I just dumped it in his main food bowl next to his main water bowl before I took a shower, intending to do the hand feeding with some wet food after I finished. I never got the chance

He is walking a bit (following me around the house when I'm gone from the room he is in too long). He still had a poop fail (He twists himself by walking around in a tight circle). But still some progress.

 

His dinner was hand fed with wet food. He had a good day, walking a bit around the apartment. Still sleeping and ending up on his butt a bit, but his peeing is really good and his pooping is getting a bit better.