Jennifer had both of her chihuahuas chipped and it was painful. The vet recommended doing one while she was already knocked out for dental work, but the other one was awake and it apparently was very painful. Jennifer cried. Perhaps it's more painful for smaller dogs? My Lola weighs an even 3 pounds and is elderly and frail. I decided not to chip her. But I did get her a tag after my son accidentally let her slip out the door once a few years ago. We made flyers and it was so extremely scary, not knowing where she was. Fortunately a stranger picked her up from the road and made the effort to look for her owners the next day. I was scared to read this thread in case the news was bad. Def, I am so glad you found your dog