when my Jeter was 14 weeks old, he got his rabies shot and he was only a little over 1 pound. I voiced my concern about the shot and even called my local Dog Warden only to be told that in Ohio it is LAW that any cat dog or ferret 3 months and older be vaccinated! I was so scared that Jeter would get ill due to the shot, I broke out in hives! My vet gives Benadryl before any shots and he kept Jeter and i at the office for about 2 1/2 hours before he sent us home with instructions on what to do in case of an Emergency. Thankfully I only live one block over from our vet, so I felt safe taking him home.
Jeter is now 21 months old and is still very small at only 2 1/2 pounds
he just got his second rabies shot and doesn't have to get any more for another 3 years!
Best of luck with your little one getting their shots! Ask for the Benadryl shot to be given before they give any vaccines too!