About how much meth did your dog eat?How much does your dog weigh?
Thanks for answering my questions.
Unfortunately, even a very small amount of methamphetamine can be fatal to a dog if ingested, especially a dog as small as yours. I understand your desire to not seek medical attention due to the fact he ate something illegal...however, your dog absolutely, positively needs medical attention immediately.
Be honest at the emergency vet and tell them what he ate. I guarantee that they have NO desire to call the local authorities because they don't care what you do in your own home, they just want to be able to provide the best supportive care for your dog until the effects of this drug wear off.
Please get him to an emergency vet right now. I hope he does okay.