my one year old golden retriever just ate a small grape today and is panting a lot i’m concerned
Grapes are one of the foods that owners should avoid giving their dogs. For more information on other foods that should be avoided, I recommend this article here for reference: https://www.vetbabble.com/dogs/food-and-diet-dogs/10-foods-bad-for-dogs/
As for your specific case, the lowest report of grape toxicity I found was 0.3 oz/kg. So, assuming your dog is over 1kg which your golden retriever should and the grape weighs 0.2 oz or less, your weight is above the threshold. However, these studies are very old and it could depend on the dog as not all dogs are susceptible to grape/raisin toxicity so this study could be biased. For the most current information on grape toxicity, I recommend calling the ASPCA poison control hotline at (888) 426-4435: https://www.aspca.org/pet-care/animal-poison-control
They are available 24×7 and can give you specific advice for your pet. They are toxicologists that have all the latest information and access to data regarding toxicities and treatments. There is a charge for their advice, but that information will be useful for your veterinarian, should a trip to the vet be warranted. If you re not able to call them or some reason, then I would encourage you to take a trip to your nearest veterinarian. Good luck!