My 7 Mo Min. Poodle Is Suddenly Lethargic And Drooling.

My 7 mo min. Poodle is suddenly lethargic and drooling. He is ordinarily very active He bowels are OK and he is peeing OK. Yesterday he got loose for 1 hr and I chased him around the neighbourhood , while he ran from park to house and back. I don't know anything harmful he could have gotten into other than deer poop Last night I sprayed his front leg with a product called "bitter Apple" to stop him licking the hair off. He did lick his leg after that. Any ideas what is going on?