I have a 7 year old Cocker Spaniel, he has been very restless for 2 days now. I am not sure what could be wrong, He won't stay still long, I haven't seen him sleep either, except when he is laying across me.

I think he maybe constipated. Anyone have any ideas what could be wrong?

With any sudden change in behavior, the best thing is a visit to the vet. More so with a physical symptom such as constipation. Do not treat him with laxatives. That could be dangerous if he has an obstructed bowel.