Could it be a pulled muscle?

My 10 year old shar-pei mix is acting strangely.  I took him for a walk on Friday evening.  It was very snowy but he seemed to like it.  When I got home, he almost immediately went and laid down , on his bed.  The next morning he was definitely out of sorts.  He was shaking, something he does when he is nervous or upset, and seemed unlike himself.  I wasn't concerned at first but after he continues this behavior I kept a close watch on him.  He wouldn't eat anything all day and when he walked he kept his head turned to the right, it seemed painful for him to look forward.  So, when he walked he was almost walking sideways.  He slept a lot which I think is good.  Today he seems much better but he is still favoring his left side.  When he walks now he actually looks forward but won't turn his head to his left. He is doing more minute muscle movements is his neck and head area than yesterday.  He also ate his food today so I'm thinking his condition is improving.  Could this just be a pulled muscle?

[ginger899]

It's possible that it is. Bounding through snow is very hard work, and if he isn't accustomed to it, he will have used muscles he didn't know he had.
The usual advice...see if there is any improvement over the next day. Obviously if not, if it gets worse, if any other symptoms develop, if he won't eat again, starts shaking,limping, vomiting, anything else....a visit to the vet is called for.
If a dog's feeling pain, it usually won't eat. If he's back to eating again it does seem like a good sign. Massage his neck, shoulder area, upper back. It might help