It's possible that your dog is suffering from vestibular disease, which affects the vestibular apparatus that controls balance.
The symptoms you describe might also be related to ingestion of a toxic substance like antifreeze, so your dog should be evaluated by a vet, immediately, in order to establish the cause of the problem and have it treated.
Lyme disease usually presents with the following symptoms:
"The most common symptom of Lyme disease in dogs is a reoccurring lameness that may shifts from leg to leg. Most commonly, it is a front leg that is effected and the lymph node on the shoulder of that leg may be enlarged. Many of the sick dogs are depressed and run fevers. Occasionally I find that the superficial lymph nodes all over the dog’s body are enlarge. It is common for infected dogs to have hot, painful joints when lameness is present. They may yelp when these joints are pressed and be quite reluctant to walk. When they do walk, they walk with a stiff shuffling gait and an arched back because of the pain. Unfortunately exercise-induced sprains, arthritis, hip dysplasia and lumbar or cervical spinal problems present very similar signs. When I am fortunate, I will notice ticks present on the dog. A classical red circular band often surrounds the tick or the place where the tick was attached. This mark is called a target or bullseye lesion. The redness follows the routs of the bacteria migrating through the skin from the site of the tick bite."
Since you say your dog is not lethargic, is eating well and has no fever, plus is not exhibiting any lameness, this may not be related to lyme disease; however, he still should be checked out by the vet ASAP, as the symptoms you describe indicate something is not right, and the underlying medical cause must be determined and treated.
I hope your dog will be fine!